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Chen YC, Hsu HL, Lee YT, Su HC, Yen SJ, Chen CH, Hsu WL, Yew TR, Yeh SR, Yao DJ, Chang YC, Chen H. An active, flexible carbon nanotube microelectrode array for recording electrocorticograms. J Neural Eng 2011; 8:034001. [PMID: 21474876 DOI: 10.1088/1741-2560/8/3/034001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A variety of microelectrode arrays (MEAs) has been developed for monitoring intra-cortical neural activity at a high spatio-temporal resolution, opening a promising future for brain research and neural prostheses. However, most MEAs are based on metal electrodes on rigid substrates, and the intra-cortical implantation normally causes neural damage and immune responses that impede long-term recordings. This communication presents a flexible, carbon-nanotube MEA (CMEA) with integrated circuitry. The flexibility allows the electrodes to fit on the irregular surface of the brain to record electrocorticograms in a less invasive way. Carbon nanotubes (CNTs) further improve both the electrode impedance and the charge-transfer capacity by more than six times. Moreover, the CNTs are grown on the polyimide substrate directly to improve the adhesion to the substrate. With the integrated recording circuitry, the flexible CMEA is proved capable of recording the neural activity of crayfish in vitro, as well as the electrocorticogram of a rat cortex in vivo, with an improved signal-to-noise ratio. Therefore, the proposed CMEA can be employed as a less-invasive, biocompatible and reliable neuro-electronic interface for long-term usage.
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Han TC, Hsu WL, Lee WD. Grain size-dependent magnetic and electric properties in nanosized YMnO3 multiferroic ceramics. NANOSCALE RESEARCH LETTERS 2011; 6:201. [PMID: 21711722 PMCID: PMC3211257 DOI: 10.1186/1556-276x-6-201] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Accepted: 03/08/2011] [Indexed: 05/31/2023]
Abstract
Magnetic and electric properties are investigated for the nanosized YMnO3 samples with different grain sizes (25 nm to 200 nm) synthesized by a modified Pechini method. It shows that magnetic and electric properties are strongly dependent on the grain size. The magnetic characterization indicates that with increasing grain size, the antiferromagnetic (AFM) transition temperature increases from 52 to 74 K. A corresponding shift of the dielectric anomaly is observed, indicating a strong correlation between the electric polarization and the magnetic ordering. Further analysis suggests that the rising of AFM transition temperature with increasing grain size should be from the structural origin, in which the strength of AFM interaction as well as the electrical polarization is dependent on the in-plane lattice parameters. Furthermore, among all samples, the sample with grain size of 95 nm is found to have the smallest leakage current density (< 1 μA/cm2).PACS: 75.50.Tt, 75.50.Ee, 75.85.+t, 77.84.-s.
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Hsu YC, Liou JM, Yang TH, Hsu WL, Lin HJ, Wu HT, Lin JT, Wang HP, Wu MS. Proton pump inhibitor versus prokinetic therapy in patients with functional dyspepsia: is therapeutic response predicted by Rome III subgroups? J Gastroenterol 2011; 46:183-90. [PMID: 20957498 DOI: 10.1007/s00535-010-0334-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 09/15/2010] [Indexed: 02/04/2023]
Abstract
BACKGROUND The comparative effectiveness of proton pump inhibitor versus prokinetic therapy in relieving the symptoms of patients with functional dyspepsia remains unknown. Whether the Rome III subgroups predict therapeutic response has not been investigated. METHODS This was an open-label, parallel randomized controlled trial. A total of 329 adult outpatients fulfilling the Rome III criteria for functional dyspepsia were randomly allocated to receive either lansoprazole 30 mg once daily (n = 166) or mosapride 5 mg thrice daily (n = 163) for 2 weeks. Enrolled patients were evaluated with the validated Hong Kong Index questionnaire for symptom severity at baseline and at the end of the trial. The primary outcome was symptom relief as defined by the Hong Kong Index, and the secondary outcome was decrease of symptom scores. Post-hoc multivariate logistic regression analysis was conducted to identify independent predictors for therapeutic response. RESULTS After 2-week therapy, 50.6% (84/166) and 47.85% (78/163) of the patients treated with lansoprazole and mosapride, respectively, achieved significant symptom relief (odds ratio 1.12, 95% confidence interval 0.72-1.72, p = 0.62). Differences in decreases of symptom scores between lansoprazole and mosapride receivers were also insignificant (-0.08, 95% confidence interval -1.25 to 1.09, p = 0.89). Therapeutic responses to either pharmacotherapy did not differ in the subgroup of patients fulfilling the criteria for epigastric pain syndrome (n = 256) or in those fulfilling the criteria for postprandial distress syndrome (n = 161). Multivariate logistic regression confirmed that the treatment allocation and Rome III subgroup were unrelated to treatment outcome. CONCLUSIONS The effectiveness of proton pump inhibitor therapy and that of prokinetic therapy in functional dyspepsia are not different, and cannot be predicted by Rome III subgroups (ClinicalTrials.gov number, NCT00663897).
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Hsu YC, Yang TH, Hsu WL, Wu HT, Cheng YC, Chiang MF, Wang CS, Lin HJ. Mosapride as an adjunct to lansoprazole for symptom relief of reflux oesophagitis. Br J Clin Pharmacol 2011; 70:171-9. [PMID: 20653670 DOI: 10.1111/j.1365-2125.2010.03696.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Reflux oesophagitis is a common clinical disorder associated with significant morbidity. Proton pump inhibitors are the current pharmacotherapy of choice, but not all treated patients achieve symptom relief. Little is known about the efficacy of mosapride, a prokinetic agent which decreases episodes of gastro-oesophageal reflux, as an adjunct to proton pump inhibitors in improving the symptoms of reflux oesophagitis. WHAT THIS STUDY ADDS Mosapride was generally not more effective than placebo as an adjunct therapy to a standard dose of lansoprazole in decreasing the symptom burden of patients with reflux oesophagitis. However, in a subgroup with more severe symptoms, combination therapy with lansoprazole and mosapride was possibly superior to monotherapy with lansoprazole. AIMS To investigate if mosapride, a prokinetic agent, was an effective adjunct to acid suppression in improving the symptoms of reflux oesophagitis. METHODS Patients (n= 96) with reflux oesophagitis were randomly assigned to either mosapride (5 mg three times daily) or placebo for 4 weeks. Symptom severity was assessed by a validated questionnaire at enrolment, 4 and 8 weeks after medication. The primary outcome for the first 4 weeks was decrease in symptom scores. After a 3 day washout period, patients initially allocated to mosapride crossed over to placebo and vice versa for the next 4 weeks. The outcome of the second phase was maintenance of symptom control. All patients received lansoprazole (30 mg once daily) throughout study. RESULTS The decreased symptom score after 4 weeks of treatment with lansoprazole and mosapride (n= 50) was 13.42 +/- 1.16 (mean +/- SEM), similar to that of lansoprazole plus placebo (10.85 +/- 1.03, n= 46), with an insignificant difference of 2.57 (95% CI -0.53, 5.67, P= 0.103). However, a sub-group analysis for patients with pre-treatment scores of >18 points (n= 48) revealed that lansoprazole plus mosapride achieved a greater reduction of symptom score than lansoprazole plus placebo (18.22 +/- 1.91 vs. 12.88 +/- 1.65; mean difference of 5.34, 95% CI 0.28, 10.40, P= 0.039). In the second phase, there was no difference between lansoprazole with mosapride or placebo in maintaining symptom control (39/44 or 86.64% vs. 41/50 or 82%, P= 0.401). Subgroup analysis for those with substantial residual symptoms revealed similar results. CONCLUSION Compared with placebo, mosapride generally does not provide additional benefit to a standard dose of lansoprazole in patients with reflux oesophagitis, except possibly in the subgroup of severely symptomatic patients.
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Hsu JP, Liu KL, Hsu WL, Yeh LH, Tseng S. Diffusiophoresis of a soft sphere normal to two parallel disks. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16037-16047. [PMID: 20843051 DOI: 10.1021/la102631q] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The diffusiophoresis of a soft spherical particle normal to two parallel disks subject to an applied ionic concentration gradient is modeled theoretically. The soft particle, which comprises a rigid core and a porous membrane layer, is capable of simulating a wide class of particles such as biocolloids and particles covered by an artificial membrane layer; a rigid particle can also be recovered as the limiting case where the membrane layer is infinitely thin. The problem considered simulates, for example, the chemotaxis of cells or microorganisms. We show that the presence of the membrane layer is capable of yielding complicated diffusiophoretic behavior when the sign of the charge carried by that layer is different from that on the surface of the rigid core of the particle. Both the sign and the magnitude of the diffusiophoretic velocity of a particle can be adjusted through varying the friction coefficient of its membrane layer. These results are of practical significance, for example, in the case where diffusiophoresis is adopted as a separation operation or as a tool to carry and/or control the rate of drug release.
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Hsu YC, Perng CL, Yang TH, Wang CS, Hsu WL, Wu HT, Cheng YC, Chiang MF, Lin HJ. A randomized controlled trial comparing two different dosages of infusional pantoprazole in peptic ulcer bleeding. Br J Clin Pharmacol 2010; 69:245-51. [PMID: 20233195 DOI: 10.1111/j.1365-2125.2009.03575.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
AIM The optimal dosage of proton pump inhibitor in bleeding peptic ulcers remains controversial. The aim was to compare the clinical effectiveness of two doses of infusional pantoprazole in peptic ulcer bleeding. METHODS Peptic ulcer patients (n= 120) with bleeding stigmata were enrolled after successful endoscopic therapy. After an initial bolus injection of 80 mg pantoprazole, patients were randomized to receive continuously infused pantoprazole at either 192 mg day(-1) or 40 mg every 6 h (i.e. 160 mg day(-1)) for 3 days. Clinical outcomes between the two groups within 14 days were compared, with 14-day recurrent bleeding regarded as the primary end-point. RESULTS Both groups (n= 60 each) were well matched in demographic and clinical factors upon entry. Bleeding totally recurred in 11 (9.2%) patients, with six (10%) in the 192 mg day(-1) group and five (8.3%) in the 160 mg day(-1) group (relative risk of bleeding recurrence between two treatments 1.2; 95% CI 0.39, 3.72). All secondary outcomes between the two groups were similar, including the amount of blood transfusion (mean 1179 ml vs. 1203 ml, P > 0.1), hospital stay (mean 9.5 days vs. 9.9 days, P > 0.1), need for surgery (n= 1 vs. n= 0, P > 0.1), and mortality (n= 1 vs. n= 0, P > 0.1). CONCLUSIONS Following endoscopic haemostasis, infusional pantoprazole at either 192 mg day(-1) or 40 mg every 6 h appear similar.
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Hsu JP, Luu XC, Hsu WL. Diffusiophoresis of an Ellipsoid along the Axis of a Cylindrical Pore. J Phys Chem B 2010; 114:8043-55. [DOI: 10.1021/jp1039157] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hsu JP, Hsu WL, Liu KL. Diffusiophoresis of a charge-regulated sphere along the axis of an uncharged cylindrical pore. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:8648-8658. [PMID: 20184368 DOI: 10.1021/la904726k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The diffusiophoresis of a charge-regulated spherical particle along the axis of a cylindrical pore is modeled. The problem considered allows us to examine simultaneously the effects of the presence of a boundary, the charge conditions on the particle surface, the thickness of the double layer, and the nature of a dispersion medium including its pH value and the diffusivities of the ionic species with respect to the diffusiophoretic behavior of a particle. We show that, in addition to the factors of double-layer polarization, electrophoresis, and the osmotic flow of solvent, the diffusiophoretic behavior of the particle can also be affected significantly by the electrical repulsive interaction between the particle and the co-ions immediately outside the double layer as they diffuse through the gap between the double layer and the pore. The last effect, which can influence the diffusiophoretic behavior of a particle both quantitatively and qualitatively, is absent in the diffusiophresis of a sphere in a spherical cavity. The competition of those effects yields many interesting results that are of practical significance in the design of a diffusiophoretic apparatus and/or the interpretation of experimental data.
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Xue B, Hsu WL, Lee JH, Lu H, Dunker AK, Uversky VN. SPA: Short peptide analyzer of intrinsic disorder status of short peptides. Genes Cells 2010; 15:635-46. [PMID: 20497238 DOI: 10.1111/j.1365-2443.2010.01407.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Disorder prediction for short peptides is important and difficult. All modern predictors have to be optimized on a preselected dataset prior to prediction. In the succeeding prediction process, the predictor works on a query sequence or its short segment. For implementing the prediction smoothly and obtaining sound prediction results, a specific length of the sequence or segment is usually required. The need of the preselected dataset in the optimization process and the length limitation in the prediction process restrict predictors' performance. To minimize the influence of these limitations, we developed a method for the prediction of intrinsic disorder in short peptides based on large dataset sampling and statistics. As evident from the data analysis, this method provides more reliable prediction of the intrinsic disorder status of short peptides.
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Hsu HL, Teng IJ, Chen YC, Hsu WL, Lee YT, Yen SJ, Su HC, Yeh SR, Chen H, Yew TR. Flexible UV-ozone-modified carbon nanotube electrodes for neuronal recording. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:2177-2181. [PMID: 20358634 DOI: 10.1002/adma.200903413] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
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Hsu JP, Liu KL, Hsu WL, Yeh LH, Tseng S. Diffusiophoresis of a Charge-Regulated Spherical Particle Normal to Two Parallel Disks. J Phys Chem B 2010; 114:2766-78. [DOI: 10.1021/jp907696t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hsu JP, Hsu WL, Ku MH, Chen ZS, Tseng S. Diffusiophoresis of a sphere along the axis of a cylindrical pore. J Colloid Interface Sci 2010; 342:598-606. [DOI: 10.1016/j.jcis.2009.10.043] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 10/19/2009] [Accepted: 10/20/2009] [Indexed: 11/26/2022]
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Hsu YC, Liou JM, Liao SC, Yang TH, Wu HT, Hsu WL, Lin HJ, Wang HP, Wu MS. Psychopathology and personality trait in subgroups of functional dyspepsia based on Rome III criteria. Am J Gastroenterol 2009; 104:2534-42. [PMID: 19532128 DOI: 10.1038/ajg.2009.328] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Functional dyspepsia is a heterogeneous symptom complex that may be subdivided into postprandial distress syndrome and epigastric pain syndrome. We aimed to investigate differences among these subgroups in psychopathological factors and personality traits. METHODS We enrolled 187 consecutive outpatients (72.2% female patients, mean age 42.6 years) with functional dyspepsia based on the Rome III criteria. Patients were interviewed and evaluated by the Brief Symptom Rating Scale and the short-form Maudsley personality inventory for severity of psychopathology and personality traits. Multiple linear regression models were built for each psychopathological dimension and personality trait to assess the independent association with each subclass diagnosis of functional dyspepsia. RESULTS There was an overlap (n=64, 34.2%) between the patients diagnosed with epigastric pain syndrome (n=157, 84.0%) and those with postprandial distress syndrome (n=94, 50.3%). Patients with symptoms compatible with both syndromes were psychopathologically more severe than either subgroup without overlapping. Multiple linear regression analysis demonstrated that the diagnosis of postprandial distress syndrome was independently associated with higher scores in overall psychopathological stress, and specifically in somatization (P=0.034), depression (P=0.028), phobia (P=0.044), and additional symptoms (P<0.001). However, epigastric pain syndrome was not associated with psychopathology. Postprandial distress was univariately associated with neuroticism, but the association was insignificant in the multivariate analysis (P=0.136). CONCLUSIONS The Rome III subgroups of functional dyspepsia significantly overlap. Patients fulfilling criteria for both subgroups had symptoms that were psychopathologically more severe than those of patients without overlapping. Diagnosis of postprandial distress syndrome, but not epigastric pain syndrome, is independently associated with psychopathological factors.
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Lin CW, Lee YT, Chang CW, Hsu WL, Chang YC, Fang W. Novel glass microprobe arrays for neural recording. Biosens Bioelectron 2009; 25:475-81. [PMID: 19726175 DOI: 10.1016/j.bios.2009.08.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 07/16/2009] [Accepted: 08/04/2009] [Indexed: 10/20/2022]
Abstract
The probe array is a useful tool for neurophysiology to detect and record neural signals. Thus, the better understanding of neural systems can be achieved. Microfabricated probes have been widely used since fine-spacing probes with well-defined electrodes in smaller footprint can be created. This study presents a novel process to realize glass 2D-microprobe array. Dielectric material like glass can provide better signal isolation capability and biocompatibility. The through silicon vias (TSVs) can also be integrated with the glass 2D-microprobe using the micromachining process. The vertical integration of chips containing glass 2D-microprobe array is realized using these silicon TSVs. The 3D-microprobe array can be easily implemented after vertical assembly of 2D-microprobe chips using bonding. In application, the 2D glass microprobe is fabricated and characterized with a low impedance of 439 kOmega at 1 kHz. The action potential of crayfish's nerve cord has successfully been recorded using the glass microprobe with peak-to-peak amplitude of 228 muV, and SNR of 46.42. The spontaneous spike of rat's cortex has also been recorded by the glass microprobe with peak-to-peak amplitude of 90 muV, and SNR of 19.72.
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Hsu WL, Chiu TH, Tai DJC, Ma YL, Lee EHY. A novel defense mechanism that is activated on amyloid-beta insult to mediate cell survival: role of SGK1-STAT1/STAT2 signaling. Cell Death Differ 2009; 16:1515-29. [PMID: 19609277 DOI: 10.1038/cdd.2009.91] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Amyloid-beta (Abeta) is known to induce apoptotic cell death and its underlying mechanism has been studied extensively, but the endogenous protection mechanism that results from Abeta insult is less known. In this study, we have found that Abeta(1-42) produced a dose-dependent decrease in cell viability and dose-dependent increase in apoptotic cell death in PC12 cells. Meanwhile, Abeta(1-42) (0.1 muM) increased the phosphorylation of serum- and glucocorticoid-inducible kinase1 (SGK1) at Ser-78 specifically. A parallel increase in ERK1/2, STAT1 and STAT2 phosphorylation and the anti-apoptotic gene Mcl-1 expression was also observed. Transfection of rat siRNAs against ERK1/2, SGK1, STAT1 and STAT2 abolished these effects of Abeta. Transfection of sgkS78D, the constitutively active SGK1, dose-dependently protected against Abeta-induced apoptosis and dose-dependently increased the expression of Mcl-1. SGK1 activation further phosphorylates STAT1 at Tyr-701 and Ser-727 directly, and activates STAT2 at Tyr-690 indirectly. Phosphorylation of STAT1/STAT2 upregulated Mcl-1 expression which in turn protected against Abeta-induced apoptosis. But Mcl-1 siRNA transfection enhanced Abeta-induced apoptosis. Mutation of SGK1 at Ser-78 blocked the effect of Abeta on STAT1/STAT2 phosphorylation and Mcl-1 expression. Further, mutation of STAT1/STAT2 prevented the effect of both Abeta and SGK1 on Mcl-1 expression. These results together showed a novel endogenous protection mechanism that is activated on Abeta insult to mediate cell survival.
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Liu SP, Hsu WL, Chang KC, Yeh JM. Enhancement of the surface and bulk mechanical properties of polystyrene through the incorporation of raw multiwalled nanotubes with the twin-screw mixing technique. J Appl Polym Sci 2009. [DOI: 10.1002/app.29526] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Zhang X, Hsu WL, Hsu JP, Tseng S. Diffusiophoresis of a Soft Spherical Particle in a Spherical Cavity. J Phys Chem B 2009; 113:8646-56. [DOI: 10.1021/jp9014417] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Liang S, Li L, Hsu WL, Pilcher MN, Uversky V, Zhou Y, Dunker AK, Meroueh SO. Exploring the molecular design of protein interaction sites with molecular dynamics simulations and free energy calculations. Biochemistry 2009; 48:399-414. [PMID: 19113835 DOI: 10.1021/bi8017043] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The significant work that has been invested toward understanding protein-protein interaction has not translated into significant advances in structure-based predictions. In particular redesigning protein surfaces to bind to unrelated receptors remains a challenge, partly due to receptor flexibility, which is often neglected in these efforts. In this work, we computationally graft the binding epitope of various small proteins obtained from the RCSB database to bind to barnase, lysozyme, and trypsin using a previously derived and validated algorithm. In an effort to probe the protein complexes in a realistic environment, all native and designer complexes were subjected to a total of nearly 400 ns of explicit-solvent molecular dynamics (MD) simulation. The MD data led to an unexpected observation: some of the designer complexes were highly unstable and decomposed during the trajectories. In contrast, the native and a number of designer complexes remained consistently stable. The unstable conformers provided us with a unique opportunity to define the structural and energetic factors that lead to unproductive protein-protein complexes. To that end we used free energy calculations following the MM-PBSA approach to determine the role of nonpolar effects, electrostatics and entropy in binding. Remarkably, we found that a majority of unstable complexes exhibited more favorable electrostatics than native or stable designer complexes, suggesting that favorable electrostatic interactions are not prerequisite for complex formation between proteins. However, nonpolar effects remained consistently more favorable in native and stable designer complexes reinforcing the importance of hydrophobic effects in protein-protein binding. While entropy systematically opposed binding in all cases, there was no observed trend in the entropy difference between native and designer complexes. A series of alanine scanning mutations of hot-spot residues at the interface of native and designer complexes showed less than optimal contacts of hot-spot residues with their surroundings in the unstable conformers, resulting in more favorable entropy for these complexes. Finally, disorder predictions revealed that secondary structures at the interface of unstable complexes exhibited greater disorder than the stable complexes.
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Hsu JP, Hsu WL, Chen ZS. Boundary effect on diffusiophoresis: spherical particle in a spherical cavity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:1772-1784. [PMID: 19123786 DOI: 10.1021/la803334a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The boundary effect on the diffusiophoretic behavior of a particle is analyzed theoretically by considering the diffusiophoresis of a charged sphere under arbitrary surface potential and double-layer thickness at an arbitrary position in an uncharged spherical cavity. We show that the phenomenon under consideration is governed by double-layer relaxation, chemiosmotic/diffusioosmotic flow, and two types of competing double-layer polarization. The presence of the cavity has a profound influence on the diffusiophoretic behavior of the particle, especially when the surface potential is high. For instance, the scaled diffusiophoretic velocity of the particle has a local maximum as the position of the particle varies; it may have a local maximum and local minimum as the thickness of the double-layer varies. The significance of the effect of double-layer relaxation depends upon the level of surface potential and magnitude of the electric Peclet number.
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Fujiwara S, Suyama A, Cologne JB, Akahoshi M, Yamada M, Suzuki G, Koyama K, Takahashi N, Kasagi E, Grant EJ, Lagarde E, Hsu WL, Furukawa K, Ohishi W, Tatsukawa Y, Neriishi K, Takahashi I, Ashizawa K, Hida A, Imaizumi M, Nagano J, Cullings HM, Katayama H, Ross NP, Kodama K, Shore RE. Prevalence of adult-onset multifactorial disease among offspring of atomic bomb survivors. Radiat Res 2009; 170:451-7. [PMID: 19024652 DOI: 10.1667/rr1392.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The first study to examine whether parental radiation exposure leads to increased heritable risk of common adult-onset multifactorial diseases (i.e., hypertension, diabetes mellitus, hypercholesterolemia, ischemic heart disease, and stroke) was conducted among 11,951 participants in the clinical examination program out of a potential of 24,673 mail survey subjects who were offspring of survivors born from May 1946 through December 1984. Logistic regression analyses demonstrated no evidence of an association between the prevalence of multifactorial diseases in the offspring and parental radiation exposure, after adjusting for age, city, gender and various risk factors. The odds ratio (OR) for a paternal dose of 1 Gy was 0.91 [95% confidence interval (CI) 0.81-1.01, P = 0.08], and that for a maternal dose of 1 Gy was 0.98 (95% CI 0.86-1.10, P = 0.71). There was no apparent effect of parental age at exposure or of elapsed time between parental exposure and birth, but male offspring had a low odds ratio (OR = 0.76 at 1 Gy) for paternal exposure, but cautious interpretation is needed for this finding. The clinical assessment of nearly 12,000 offspring of A-bomb survivors who have reached a median age of about 50 years provided no evidence for an increased prevalence of adult-onset multifactorial diseases in relation to parental radiation exposure.
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Lu CH, Huang SW, Lai YL, Lin CP, Shih CH, Huang CC, Hsu WL, Hwang JK. On the relationship between the protein structure and protein dynamics. Proteins 2008; 72:625-34. [PMID: 18247347 DOI: 10.1002/prot.21954] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recently, we have developed a method (Shih et al., Proteins: Structure, Function, and Bioinformatics 2007;68: 34-38) to compute correlation of fluctuations of proteins. This method, referred to as the protein fixed-point (PFP) model, is based on the positional vectors of atoms issuing from the fixed point, which is the point of the least fluctuations in proteins. One corollary from this model is that atoms lying on the same shell centered at the fixed point will have the same thermal fluctuations. In practice, this model provides a convenient way to compute the average dynamical properties of proteins directly from the geometrical shapes of proteins without the need of any mechanical models, and hence no trajectory integration or sophisticated matrix operations are needed. As a result, it is more efficient than molecular dynamics simulation or normal mode analysis. Though in the previous study the PFP model has been successfully applied to a number of proteins of various folds, it is not clear to what extent this model will be applied. In this article, we have carried out the comprehensive analysis of the PFP model for a dataset comprising 972 high-resolution X-ray structures with pairwise sequence identity <or=25%. We found that in most cases the PFP model works well. However, in case of proteins comprising multiple domains, each domain should be treated separately as an independent dynamical module with its own fixed point; and in case of the protein complex comprising a number of subunits, if functioning as a biological unit, the whole complex should be considered as one single dynamical module with one fixed point. Under such considerations, the resultant correlation coefficient between the computed and the X-ray structural B-factors for the data set is 0.59 and 75% (727/972) of proteins with a correlation coefficient >or=0.5. Our result shows that the fixed-point model is indeed quite general and will be a useful tool for high throughput analysis of dynamical properties of proteins.
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Lee CY, Wey SP, Liao MH, Hsu WL, Wu HY, Jan TR. A comparative study on cannabidiol-induced apoptosis in murine thymocytes and EL-4 thymoma cells. Int Immunopharmacol 2008; 8:732-40. [PMID: 18387516 DOI: 10.1016/j.intimp.2008.01.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Revised: 01/17/2008] [Accepted: 01/17/2008] [Indexed: 10/22/2022]
Abstract
It has been shown that leukemia and glioma cells are sensitive to cannabidiol (CBD)-induced apoptosis, whereas primary monocytes and glia cells are relatively insensitive. In the current study, the cellular events and sensitivity to CBD-induced apoptosis between murine thymocytes and EL-4 thymoma cells were compared. Cannabidiol markedly induced apoptosis in a time- and concentration-related manner in both cells. The efficacy of CBD to induce apoptosis was comparable between the 2 types of T cells, whereas CBD induced apoptosis in thymocytes with a slightly greater potency than in EL4 cells. Time-course analyses revealed CBD-mediated apoptosis occurred earlier in EL-4 cells than that in thymocytes. An increased level of cellular reactive oxygen species (ROS) was detected in both cells with the peak response at 2 h post CBD treatment. Concordantly, CBD triggered a gradual diminishment in the cellular thiols. The presence of N-acetyl-L-cysteine (NAC), a precursor of glutathione, markedly attenuated the induction of apoptosis, and restored the diminished levels of cellular thiols. The results demonstrated that both thymocytes and EL-4 thymoma cells were susceptible to CBD-induced apoptosis and that ROS played a critical role in the apoptosis induction.
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98
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Yang MJ, Tseng JY, Hsu WL. Magnetic resonance imaging as a diagnostic tool in pregnancy with appendiceal abscess. J Chin Med Assoc 2007; 70:345-7. [PMID: 17698435 DOI: 10.1016/s1726-4901(08)70016-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Abdominal pain presenting itself during pregnancy may be multifactorial, requiring immediate attention and care. In cases of intractable pain without obstetrical condition, surgical abdominal exploration is widely advised. However, we present a case where a 30-year-old, gravida 1, para 0, female complained of persistent right abdominal pain during her 25th week of pregnancy. Ultrasound revealed a right upper quadrant cystic mass and magnetic resonance imaging was arranged with compatible findings. Final impression of appendiceal abscess was determined. Broad-spectrum antibiotics were administered and the patient was discharged in stable condition after 10 days of conservative treatment. She delivered a healthy baby boy at her 40th week of gestation uneventfully.
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Yang KL, Chu CC, Huang CH, Lin SZ, Hsu WL, Liu DW, Lin PY. Discovery of HLA-DRB1*0331 in a Taiwanese marrow donor and the importance of sequence-based typing in a rare or previously unrecognized allele. Int J Immunogenet 2007; 34:91-5. [PMID: 17373933 DOI: 10.1111/j.1744-313x.2007.00662.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We describe here a novel HLA-DRB1* allele, DRB1*0331, observed from a Taiwanese bone marrow donor using DNA sequence-based typing (SBT) method. The 'new' allele differs from DRB1*0306 and DRB1*0325 by one nucleotide at positions 196 and 227, respectively. Nucleotide mutations caused amino acid substitutions from N to Y at codon 37 and from F to Y at codon 47, as compared with amino acid sequence encoded by the DRB1*030101 allele. The donor was first typed as DRB1*0403/0406/0439/0441/0446/0451/0452 (NMDP code DRB1*04XX) and DRB1*0304/0323/0325 (NMDP code DRB1*03APDA) by sequence-specific oligonucleotide (SSO) typing kit. Subsequent typing of the donor by high-resolution sequence-specific primer (SSP) protocol indicated DRB1*0403 and DRB1*0306. The anomalous result of DRB1*03 was resolved by SBT and recognized as DRB1*0331. We concluded that SSP or SSO alone may mistype a precedent unrecognized allele and that two different typing techniques or SBT may have to be employed to safe guard true HLA typing when rare alleles are encountered at the first time.
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Juang CM, Yu KJ, Chou P, Yen MS, Twu NF, Horng HC, Hsu WL. Efficacy Analysis of Trans-obturator Tension-free Vaginal Tape (TVT-O) Plus Modified Ingelman-Sundberg Procedure versus TVT-O Alone in the Treatment of Mixed Urinary Incontinence: A Randomized Study. Eur Urol 2007; 51:1671-8; discussion 1679. [PMID: 17254697 DOI: 10.1016/j.eururo.2007.01.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2006] [Accepted: 01/05/2007] [Indexed: 10/23/2022]
Abstract
OBJECTIVE The treatment of women with mixed urinary incontinence still poses a great challenge. This study evaluated surgical outcomes of combined trans-obturator tension-free vaginal tape (TVT-O) and modified Ingelman-Sundberg (IS) procedure for the treatment of mixed urinary incontinence. METHODS A randomized controlled trial was conducted. Ninety-six women diagnosed with mixed incontinence were randomized, with 49 allocated to TVT-O plus IS and 47 to TVT-O alone. A baseline urodynamic study and evaluation of quality of life (QOL) was conducted. The primary outcome measure was objective assessment of surgical outcomes, and the secondary outcome measure was warning time. RESULTS Objective surgical response rate was significantly higher in the TVT-O plus IS group than in the TVT-O alone group (84.8% vs. 62.8%; p=0.019). Furthermore, a significant increase in warning time was observed in the TVT-O plus IS group (from 3.9 to 9.4 min; p=0.006), but the increase in warning time within the TVT-O alone group was not statistically significant (from 4.3 to 4.5 min; p=0.695). Postoperative complications were similar in the two study groups with respect to pelvic hematoma, nerve injury, sepsis, mesh erosion, and fistula formation. However, fever occurred more frequently in the TVT-O plus IS group (30.4% vs. 20.9%; p=0.026). CONCLUSIONS Mixed urinary incontinence can potentially be treated with a one-step combined surgery using trans-obturator sling plus modified IS procedure. Although surgical time and blood loss were significantly increased in the TVT-O plus IS group, overall morbidity was not significantly increased.
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