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Find video protocols related to scientific articles indexed in Pubmed.
Asthma in patients with attention-deficit/hyperactivity disorder: A nationwide population-based study.
Ann Clin Psychiatry
PUBLISHED: 11-18-2014
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Asthma symptoms can interrupt daily activities, disturb sleep, and increase the risk of a child having an attention deficit or irritability, which also are symptoms of attention-deficit/hyperactivity disorder (ADHD). Previous studies have shown conflicting results regarding the association between ADHD and asthma. This study investigates the possible correlation between asthma and ADHD.
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Gait and balance analysis for patients with Alzheimer's disease using an inertial-sensor-based wearable instrument.
IEEE J Biomed Health Inform
PUBLISHED: 11-07-2014
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Despite patients with Alzheimer's disease (AD) were reported of revealing gait disorders and balance problems, there is still lack of objective quantitative measurement of gait patterns and balance capability of AD patients. Based on an inertial-sensor-based wearable device, this paper develops gait and balance analyzing algorithms to obtain quantitative measurements and explores the essential indicators from the measurements for AD diagnosis. The gait analyzing algorithm is composed of stride detection followed by gait cycle decomposition so that gait parameters are developed from the decomposed gait details. On the other hand, the balance is measured by the sway speed in anterior-posterior (AP) and medial-lateral (ML) directions of the projection path of body's center of mass (COM). These devised gait and balance parameters were explored on twenty-one AD patients and fifty healthy controls (HCs). Special evaluation procedure including single-task and dual-task walking experiments for observing the cognitive function and attention is also devised for the comparison of AD and HC groups. Experimental results show that the wearable instrument with the designed gait and balance analyzing system is a promising tool for automatically analyzing gait information and balance ability, serving as assistant indicators for early diagnosis of AD.
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4-Coumaroyl and Caffeoyl Shikimic Acids Inhibit 4-Coumaric Acid: Coenzyme A Ligases and Modulate Metabolic Flux for 3-Hydroxylation in Monolignol Biosynthesis of Populus trichocarpa.
Mol Plant
PUBLISHED: 10-23-2014
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In a number of plant species, downregulation of 4-coumaric acid: coenzyme A ligase (4CL) can reduce lignin content. In lignin precursor (monolignol) biosynthesis during stem wood formation in Populus trichocarpa, two enzymes Ptr4CL3 and Ptr4CL5 catalyze the CoA ligation of 4-coumaric acid to 4-coumaroyl-CoA and caffeic acid to caffeoyl-CoA. CoA ligation of 4-coumaric acid is essential for the 3-hydroxylation of 4-coumaroyl shikimic acid. This hydroxylation results from sequential reactions of 4-hydroxycinnamoyl-CoA: shikimic acid hydroxycinnamoyl transferases (PtrHCT1 and PtrHCT6) and 4-coumaric acid 3-hydroxylase 3 (PtrC3H3). Alternatively, 3-hydroxylation of 4-coumaric acid to caffeic acid may occur through an enzyme complex of cinnamic acid 4-hydroxylase 1 and 2 (PtrC4H1 and PtrC4H2) and PtrC3H3. We found that 4-coumaroyl and caffeoyl shikimic acids are inhibitors of Ptr4CL3 and Ptr4CL5. 4-Coumaroyl shikimic acid strongly inhibits formation of 4-coumaroyl-CoA and caffeoyl-CoA. Caffeoyl shikimic acid inhibits only formation of 4-coumaroyl-CoA. 4-coumaroyl and caffeoyl shikimic acids both act as competitive and uncompetitive inhibitors. Estimates of metabolic flux in wildtype and PtrC3H3 downregulated P. trichocarpa transgenics have been made using LC-MS/MS based absolute protein and metabolite quantification, mass action kinetics and inhibition equations. Inhibition by 4-coumaroyl and caffeoyl shikimic acids may play significant regulatory roles when these inhibitors accumulate.
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Curcumin enhances the production of major structural components of elastic fibers, elastin, and fibrillin-1, in normal human fibroblast cells.
Biosci. Biotechnol. Biochem.
PUBLISHED: 10-22-2014
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Curcumin is the major component of the yellow extract derived from the rhizome of the Curcuma longa, which is also a main bioactive polyphenol and has been generally used as a spice, food additive, and herbal medicine. In this presented study, we found that curcumin can enhance the production of major structural components of elastic fibers, elastin, and fibrillin-1, in normal human fibroblast cells via increasing ELN and FBN1 promoters' activities. With 2 ?M curcumin treatment, the enhanced tropoelastin and fibrillin-1 protein amounts in Detroit 551 cells were approximately 134 and 130% of control, respectively. Therefore, our results demonstrated that curcumin may be used as a functional compound and applied to drugs, foods, and cosmetics in the future.
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Fabrication and characterization of back-side illuminated InGaN/GaN solar cells with periodic via-holes etching and Bragg mirror processes.
Opt Express
PUBLISHED: 10-17-2014
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In this study, the design and fabrication schemes of back-side illuminated InGaN/GaN solar cells with periodic via-holes etching and Bragg mirror processes are presented. Compared to typical front-side illuminated solar cells, the improvements of open-circuit voltage (Voc) from 1.88 to 1.94 V and short-circuit current density (Jsc) from 0.84 to 1.02 mA/cm2 are observed. Most significantly, the back-side illuminated InGaN/GaN solar cells exhibit an extremely high fill factor up to 85.5%, leading to a conversion efficiency of 1.69% from 0.66% of typical front-side illuminated solar cells under air mass 1.5 global illuminations. Moreover, the effects of bottom Bragg mirrors on the photovoltaic characteristics of back-side illuminated solar cells are studied by an advanced simulation program. The results show that the Jsc could further be improved with a factor of 10% from the original back-side illuminated solar cell by the structure optimization of bottom Bragg mirrors.
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Fusion May Not Be a Necessary Procedure for Surgically Treated Burst Fractures of the Thoracolumbar and Lumbar Spines: A Follow-up of at Least Ten Years.
J Bone Joint Surg Am
PUBLISHED: 10-17-2014
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The surgical results of treating thoracolumbar and lumbar burst fractures were reported to be comparable between patients with and without fusion in an intermediate-term follow-up. To our knowledge, no prior report has compared the results of fusion and non-fusion with long-term follow-up.
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Noninvasive Saliva-based EGFR Gene Mutation Detection in Patients with Lung Cancer.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 10-16-2014
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Constitutive activation of the epidermal growth factor receptor (EGFR) is prevalent in epithelial cancers, particularly in non-small cell lung carcinoma (NSCLC). Mutations identified in EGFR predict the sensitivity to EGFR-targeted therapy. Detection of these mutations is mainly based on tissue biopsy, which is invasive, expensive, and time consuming.
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Synthesis and SAR studies of novel 6,7,8-substituted 4-substituted benzyloxyquinolin-2(1H)-one derivatives for anticancer activity.
Br. J. Pharmacol.
PUBLISHED: 09-29-2014
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4-Phenylquinolin-2(1H)-one (4-PQ) derivatives can induce cancer cell apoptosis. Additional new 4-PQ analogs were investigated as more effective, less toxic antitumor agents.
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A simple improved-throughput xylem protoplast system for studying wood formation.
Nat Protoc
PUBLISHED: 08-21-2014
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Isolated protoplasts serve as a transient expression system that is highly representative of stable transgenics in terms of transcriptome responses. They can also be used as a cellular system to study gene transactivation and nucleocytoplasmic protein trafficking. They are particularly useful for systems studies in which stable transgenics and mutants are unavailable. We present a protocol for the isolation and transfection of protoplasts from wood-forming tissue, the stem-differentiating xylem (SDX), in the model woody plant Populus trichocarpa. The method involves tissue preparation, digestion of SDX cell walls, protoplast isolation and DNA transfection. Our approach is markedly faster and provides better yields than previous protocols; small (milligrams)- to large (20 g)-scale SDX preparations can be achieved in ~60 s, with isolation of protoplasts and their subsequent transfection taking ~50 min. Up to ten different samples can be processed simultaneously in this time scale. Our protocol gives a high yield (~2.5 × 10(7) protoplasts per g of SDX) of protoplasts sharing 96% transcriptome identity with intact SDX.
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A robust chromatin immunoprecipitation protocol for studying transcription factor-DNA interactions and histone modifications in wood-forming tissue.
Nat Protoc
PUBLISHED: 08-21-2014
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Woody cells and tissues are recalcitrant to standard chromatin immunoprecipitation (ChIP) procedures. However, we recently successfully implemented ChIP in wood-forming tissue of the model woody plant Populus trichocarpa. Here we provide the detailed ChIP protocol optimized for wood-forming tissue that we used in those studies. By using stem-differentiating xylem (SDX; a wood-forming tissue), we identified all steps that were ineffective in standard ChIP protocols and systematically modified them to develop and optimize a robust ChIP protocol. The protocol includes tissue collection, cross-linking, nuclear isolation, chromatin extraction, DNA fragmentation, immunoprecipitation, DNA purification and sequence analysis. The protocol takes 2.5 d to complete and allows a robust 8-10-fold enrichment of transcription factor (TF)-bound genomic fragments (~150 ng/g of SDX) over nonspecific DNAs. The enriched DNAs are of high quality and can be used for subsequent PCR and DNA-seq analyses. We used this protocol to identify genome-wide specific TF-DNA interactions during wood formation and histone modifications associated with regulation of wood formation. Our protocol, which may be suitable for many tissue types, is so far the only working ChIP system for wood-forming tissue.
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Bone-prosthesis composite with rotating hinged-knee prosthesis in limb salvage surgery for high-grade sarcoma around the knee.
J Arthroplasty
PUBLISHED: 08-01-2014
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Bone prosthesis composite (BPC) had been widely-used in reconstruction after wide excision of malignant tumors around the knee. However, implant selection for BPC remains a dilemma. Forty-one patients with high-grade malignant bone tumors around the knee who underwent excision and reconstruction with BPC and rotating hinged knee (RHK) prosthesis were included. The mean follow-up time was 54months (range, 31-78months). The average Musculoskeletal Tumor Society Rating score was 93.4% (range, 73-100%). The mean range of motion was 125°. Complications included 2 local recurrences, 2 nonunions, and 1 peri-prosthetic fracture. The reconstruction with BPC using the RHK prosthesis provided consistently good functional results with a low complication rate. The RHK prosthesis is a promising choice for BPC reconstruction.
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Predictive factors of silent reflux in subjects with erosive esophagitis.
Dig Liver Dis
PUBLISHED: 07-21-2014
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Asymptomatic erosive esophagitis by definition is a condition lacking any reflux symptom.
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A meta-learning approach for B-cell conformational epitope prediction.
BMC Bioinformatics
PUBLISHED: 07-11-2014
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BackgroundOne of the major challenges in the field of vaccine design is identifying B-cell epitopes in continuously evolving viruses. Various tools have been developed to predict linear or conformational epitopes, each relying on different physicochemical properties and adopting distinct search strategies. We propose a meta-learning approach for epitope prediction based on stacked and cascade generalizations. Through meta learning, we expect a meta learner to be able integrate multiple prediction models, and outperform the single best-performing model. The objective of this study is twofold: (1) to analyze the complementary predictive strengths in different prediction tools, and (2) to introduce a generic computational model to exploit the synergy among various prediction tools. Our primary goal is not to develop any particular classifier for B-cell epitope prediction, but to advocate the feasibility of meta learning to epitope prediction. With the flexibility of meta learning, the researcher can construct various meta classification hierarchies that are applicable to epitope prediction in different protein domains.ResultsWe developed the hierarchical meta-learning architectures based on stacked and cascade generalizations. The bottom level of the hierarchy consisted of four conformational and four linear epitope prediction tools that served as the base learners. To perform consistent and unbiased comparisons, we tested the meta-learning method on an independent set of antigen proteins that were not used previously to train the base epitope prediction tools. In addition, we conducted correlation and ablation studies of the base learners in the meta-learning model. Low correlation among the predictions of the base learners suggested that the eight base learners had complementary predictive capabilities. The ablation analysis indicated that the eight base learners differentially interacted and contributed to the final meta model. The results of the independent test demonstrated that the meta-learning approach markedly outperformed the single best-performing epitope predictor.ConclusionsComputational B-cell epitope prediction tools exhibit several differences that affect their performances when predicting epitopic regions in protein antigens. The proposed meta-learning approach for epitope prediction combines multiple prediction tools by integrating their complementary predictive strengths. Our experimental results demonstrate the superior performance of the combined approach in comparison with single epitope predictors.
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Wake-up test in total hip arthroplasty with high-riding developmental dysplasia.
Orthopedics
PUBLISHED: 07-04-2014
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Total hip arthroplasty (THA) for patients with Crowe type IV developmental dysplasia of the hip is technically challenging. This group of patients has a higher incidence of nerve injury during THA. Although neurophysiologic intraoperative monitoring has been developed to provide nerve monitoring, it is not always available. The wake-up test has been used for intraoperative spinal cord monitoring during major spinal surgery, but no study has reported the use of the wake-up test for neurologic monitoring during THA in patients with severe developmental dysplasia of the hip. The authors retrospectively reviewed 22 THA procedures in 20 patients with Crowe type IV developmental dysplasia of the hip who underwent the wakeup test during THA. In the current study, 1 patient could not dorsiflex her foot during the wake-up test. Therefore, the authors immediately reduced the length of limb lengthening by 1 cm. Postoperative drop foot and numbness occurred but resolved completely 2 months later. None of the patients who showed no deficits in motion of the feet during the intraoperative wake-up test had signs of postoperative nerve injury. In the current study, there was no false-positive or false-negative finding. The authors concluded that the wake-up test, which is simple, safe, and reliable, is a useful technique and a possible alternative to neurophysiologic intraoperative monitoring in checking nerve function during THA in patients with severe developmental dysplasia of the hip.
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The emerging landscape of salivary diagnostics.
Oral Health Dent Manag
PUBLISHED: 07-03-2014
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Saliva as a diagnostic tool provides a noninvasive, simple and low-cost method for disease detection and screening. Saliva collection is more practical and comfortable compared with other invasive methods, and saliva can be a desirable body fluid for biomarker detection in clinical applications. The integration of omics methods has allowed accurate detection and quantification of transcripts found in saliva and a group of biomarkers has been discovered and validated in a series of studies. Here we review recent developments in salivary diagnostics that have been accomplished using salivaomics, the mechanisms of saliva diagnostics, as well as the translational and clinical application of saliva biomarkers.
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Mechanical reinforcement of epoxy with self-assembled synthetic clay in smectic order.
ACS Appl Mater Interfaces
PUBLISHED: 06-27-2014
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Epoxy films containing self-assembled 2D colloidal ?-zirconium phosphate nanoplatelets (ZrP) in smectic order were prepared using a simple, energy-efficient fabrication process suitable to industrial processing. The ZrP nanoplatelets form a chiral smectic mesophase with simultaneous lamellar order and helical arrangements in epoxy. The epoxy nanocomposite films are transparent and flexible and exhibit exceptionally high tensile modulus and strength. The findings have broad implications for development of multifunctional materials for engineering applications.
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Type II GaSb quantum ring solar cells under concentrated sunlight.
Opt Express
PUBLISHED: 06-13-2014
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A type II GaSb quantum ring solar cell is fabricated and measured under the concentrated sunlight. The external quantum efficiency confirms the extended absorption from the quantum rings at long wavelength coinciding with the photoluminescence results. The short-circuit current of the quantum ring devices is 5.1% to 9.9% more than the GaAs reference's under various concentrations. While the quantum ring solar cell does not exceed its GaAs counterpart in efficiency under one-sun, the recovery of the open-circuit voltages at higher concentration helps to reverse the situation. A slightly higher efficiency (10.31% vs. 10.29%) is reported for the quantum ring device against the GaAs one.
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Tunable microwave generation of a monolithic dual-wavelength distributed feedback laser.
Opt Express
PUBLISHED: 06-13-2014
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The dynamic behavior of a monolithic dual-wavelength distributed feedback laser was fully investigated and mapped. The combination of different driving currents for master and slave lasers can generate a wide range of different operational modes, from single mode, period 1 to chaos. Both the optical and microwave spectrum were recorded and analyzed. The detected single mode signal can continuously cover from 15GHz to 50GHz, limited by photodetector bandwidth. The measured optical four-wave-mixing pattern indicates that a 70GHz signal can be generated by this device. By applying rate equation analysis, the important laser parameters can be extracted from the spectrum. The extracted relaxation resonant frequency is found to be 8.96GHz. With the full operational map at hand, the suitable current combination can be applied to the device for proper applications.
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Novel target genes responsive to apoptotic activity by Ocimum gratissimum in human osteosarcoma cells.
Am. J. Chin. Med.
PUBLISHED: 05-30-2014
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Osteosarcoma (OS) is a type of bone cancer. Eighty percent of this tumor will metastasize to the lungs or liver, and as a result, patients generally need chemotherapy to improve survival possibility. Recently, antitumor activity has been reported in Ocimum gratissimum aqueous extract (OGE), which has been the focus of recent extensive studies on therapeutic strategies due to its antioxidant properties. We performed pharmacogenomics analyses for the effect of OGE on human osteosarcoma U2-OS and HOS cell growth. Cell viability, Western blot and flow cytometry analysis were performed before performing pharmacogenomics analyses for the effect of OGE on human osteosarcoma U2-OS and HOS cell growth, including cDNA microarray and RT-PCR assays. Cell viability assays revealed that OGE significantly and dose-dependently decreased the viability of U2-OS and HOS cells. Increases in cell shrinkage, Sub-G1 fragments and the activation of caspase 3 indicated that OGE induced cell apoptosis in U2-OS and HOS cells. There was no change in human osteoblast hFOS cells. cDNA microarray assay demonstrated that the expression of cell cycle regulators, apoptosis-related factors and cell proliferation markers were all modified by OGE treatment. RT-PCR analysis also confirmed the down-regulation of SKA2 and BUB1B, and the up-regulation of PPP1R15A, SQSTM1, HSPA1B, and DDIT4 by OGE treatment. The finding of anticancer activity in OGE and the identification of some potential target genes raise the expectation that OGE may become a useful therapeutic drug for human OS.
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Using Cluster Analysis to Identify Phenotypes and Validation of Mortality in Men with COPD.
Lung
PUBLISHED: 04-29-2014
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Cluster analysis has been proposed to examine phenotypic heterogeneity in chronic obstructive pulmonary disease (COPD). The aim of this study was to use cluster analysis to define COPD phenotypes and validate them by assessing their relationship with mortality.
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Highly efficient multiple-layer CdS quantum dot sensitized III-V solar cells.
J Nanosci Nanotechnol
PUBLISHED: 04-23-2014
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In this review, the concept of utilization of solar spectrum in order to increase the solar cell efficiency is discussed. Among the three mechanisms, down-shifting effect is investigated in detail. Organic dye, rare-earth minerals and quantum dots are three most popular down-shift materials. While the enhancement of solar cell efficiency was not clearly observed in the past, the advances in quantum dot fabrication have brought strong response out of the hybrid platform of a quantum dot solar cell. A multiple layer structure, including PDMS as the isolation layer, is proposed and demonstrated. With the help of pulse spray system, precise control can be achieved and the optimized concentration can be found.
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A highly efficient hybrid GaAs solar cell based on colloidal-quantum-dot-sensitization.
Sci Rep
PUBLISHED: 04-10-2014
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This paper presents a hybrid design, featuring a traditional GaAs-based solar cell combined with various colloidal quantum dots. This hybrid design effectively boosts photon harvesting at long wavelengths while enhancing the collection of photogenerated carriers in the ultraviolet region. The merits of using highly efficient semiconductor solar cells and colloidal quantum dots were seamlessly combined to increase overall power conversion efficiency. Several photovoltaic parameters, including short-circuit current density, open circuit voltage, and external quantum efficiency, were measured and analyzed to investigate the performance of this hybrid device. Offering antireflective features at long wavelengths and luminescent downshifting for high-energy photons, the quantum dots effectively enhanced overall power conversion efficiency by as high as 24.65% compared with traditional GaAs-based devices. The evolution of weighted reflectance as a function of the dilution factor of QDs was investigated. Further analysis of the quantum efficiency response showed that the luminescent downshifting effect can be as much as 6.6% of the entire enhancement of photogenerated current.
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Citrus medica var. sarcodactylis (Foshou) activates fibroblast growth factor-2 signaling to induce migration of RSC96 Schwann cells.
Am. J. Chin. Med.
PUBLISHED: 04-09-2014
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Factors that enhance the intrinsic growth potential of neurons play a major role in the regeneration and repair of adult neurons following an injury. Fibroblast growth factor (FGF-2) is one of the key players in the origin and growth of neuronal and glial cells through autocrine and paracrine signaling. Water extract of Citrus medica var. sarcodactylis (fingered citron, foshou), which is been used effectively as a Chinese herbal medicine, was found to activate the FGF-2 promoter in transgenic luciferase expression models. Foshou treatment on Schwann cells (RSC96) transfected with luciferase reporter plasmid under a FGF-2 promoter was found to induce the FGF-2 promoter and showed enhanced luciferase expression. The FGF-2 expression was accompanied with an increase in the expression of proteins involved in cell migration and cell proliferation in a dose dependent manner. Therefore, foshou potentially enhances nerve regeneration by inducing the Schwann cell proliferation and migration.
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White light emitting diodes with enhanced CCT uniformity and luminous flux using ZrO2 nanoparticles.
Nanoscale
PUBLISHED: 04-08-2014
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To enhance the uniformity of correlated color temperature (CCT) and luminous flux, we integrated ZrO2 nanoparticles into white light-emitting diodes. This novel packaging scheme led to a more than 12% increase in luminous flux as compared to that in conventional dispensing structures. This was attributed to the scattering effect of ZrO2 nanoparticles, which enhanced the utilization of blue light. Moreover, the CCT deviation was reduced from 522 to 7 K in a range of -70 to +70°, and essentially eliminated the yellow ring phenomenon. The haze measurement indicated strong scattering across the visible spectrum in the presence of ZrO2 in the silicone layer, and this finding also substantiates our claim. In addition, the chromaticity coordinate shift was steady in the ZrO2 dispensing package structure as the drive current increased, which is crucial for indoor lighting. Combined with its low cost, easy fabrication, and superior optical characteristics, ZrO2 nanoparticles can be an effective performance enhancer for the future generation of white light-emitting devices.
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Biomechanical analysis and design of a dynamic spinal fixator using topology optimization: a finite element analysis.
Med Biol Eng Comput
PUBLISHED: 03-31-2014
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Surgeons often use spinal fixators to manage spinal instability. Dynesys (DY) is a type of dynamic fixator that is designed to restore spinal stability and to provide flexibility. The aim of this study was to design a new spinal fixator using topology optimization [the topology design (TD) system]. Here, we constructed finite element (FE) models of degenerative disc disease, DY, and the TD system. A hybrid-controlled analysis was applied to each of the three FE models. The rod structure of the topology optimization was modelled at a 39 % reduced volume compared with the rigid rod. The TD system was similar to the DY system in terms of stiffness. In contrast, the TD system reduced the cranial adjacent disc stress and facet contact force at the adjacent level. The TD system also reduced pedicle screw stresses in flexion, extension, and lateral bending.
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Improvement of emission uniformity by using micro-cone patterned PDMS film.
Opt Express
PUBLISHED: 03-26-2014
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Micro-patterned PDMS film was fabricated and combined with LED chip on board (COB) package to improve the emission uniformity of LED chip. The micro scale patterned sapphire substrate (PSS) was used as a mold to fabricate micro-cone patterned PDMS (MC-PDMS) film. A strong scattering effect from this MC-PDMS film can be verified by the high haze ratio and the Bi-directional Transmission effect. The angle dependent color temperature measurement system was used to measure the ?CCT of COB with and without MC-PDMS. The measurement results indicate that the ?CCT was reduced from 1025K to 428K. This improvement can effectively eliminate the yellow ring effect of LED chip. This technology can be thus considered as a cost-effective way for the next generation of light source packages.
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Flexible-textured polydimethylsiloxane antireflection structure for enhancing omnidirectional photovoltaic performance of Cu(In,Ga)Se2 solar cells.
Opt Express
PUBLISHED: 03-26-2014
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Because of the Sun's movement across the sky, broadband and omnidirectional light harvesting is a major development in photovoltaic technology. This study reports the fabrication and characterization of flexible-textured polydimethylsiloxane (PDMS) film on Cu(In,Ga)Se2 (CIGS) solar cells, which is one of the simplest and cheapest peel-off processes for fabricating a three-dimensional structure. A cell containing a textured PDMS film enhanced the short-circuit current density from 22.12 to 23.93 mA/cm2 in a simulated one-sun scenario. The omnidirectional antireflection of CIGS solar cells containing various PDMS films is also investigated. This study uses an angle-resolved reflectance spectroscope to investigate the omnidirectional and broadband optical properties of the proposed PDMS film. This improvement in light harvesting is attributable to the scattering of the PDMS film and the gradual refractive index profile between the PDMS microstructures and air. The flexible-textured PDMS film is suitable for creating an antireflective coating for a diverse range of photovoltaic devices.
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Complete proteomic-based enzyme reaction and inhibition kinetics reveal how monolignol biosynthetic enzyme families affect metabolic flux and lignin in Populus trichocarpa.
Plant Cell
PUBLISHED: 03-11-2014
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We established a predictive kinetic metabolic-flux model for the 21 enzymes and 24 metabolites of the monolignol biosynthetic pathway using Populus trichocarpa secondary differentiating xylem. To establish this model, a comprehensive study was performed to obtain the reaction and inhibition kinetic parameters of all 21 enzymes based on functional recombinant proteins. A total of 104 Michaelis-Menten kinetic parameters and 85 inhibition kinetic parameters were derived from these enzymes. Through mass spectrometry, we obtained the absolute quantities of all 21 pathway enzymes in the secondary differentiating xylem. This extensive experimental data set, generated from a single tissue specialized in wood formation, was used to construct the predictive kinetic metabolic-flux model to provide a comprehensive mathematical description of the monolignol biosynthetic pathway. The model was validated using experimental data from transgenic P. trichocarpa plants. The model predicts how pathway enzymes affect lignin content and composition, explains a long-standing paradox regarding the regulation of monolignol subunit ratios in lignin, and reveals novel mechanisms involved in the regulation of lignin biosynthesis. This model provides an explanation of the effects of genetic and transgenic perturbations of the monolignol biosynthetic pathway in flowering plants.
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Cytotoxic effects of 15d-PGJ2 against osteosarcoma through ROS-mediated AKT and cell cycle inhibition.
Oncotarget
PUBLISHED: 02-26-2014
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Polo-like kinase 1 (PLK1), a critical cell cycle regulator, has been identified as a potential target in osteosarcoma (OS). 15-deoxy-?12, 14-prostaglandin J2 (15d-PGJ2), a prostaglandin derivative, has shown its anti-tumor activity by inducing apoptosis through reactive oxygen species (ROS)-mediated inactivation of v-akt, a murine thymoma viral oncogene homolog, (AKT) in cancer cells. In the study analyzing its effects on arthritis, 15d-PGJ2 mediated shear-induced chondrocyte apoptosis via protein kinase A (PKA)-dependent regulation of PLK1. In this study, the cytotoxic effect and mechanism underlying 15d-PGJ2 effects against OS were explored using OS cell lines. 15d-PGJ2 induced significant G2/M arrest, and exerted time- and dose-dependent cytotoxic effects against all OS cell lines. Western blot analysis showed that both AKT and PKA-PLK1 were down-regulated in OS cell lines after treatment with 15d-PGJ2. In addition, transfection of constitutively active AKT or PLK1 partially rescued cells from 15d-PGJ2-induced apoptosis, suggesting crucial roles for both pathways in the anti-cancer effects of 15d-PGJ2. Moreover, ROS generation was found treatment with 15d-PGJ2, and its cytotoxic effect could be reversed with N-acetyl-l-cysteine. Furthermore, inhibition of JNK partially rescued 15d-PGJ2 cytotoxicity. Thus, ROS-mediated JNK activation may contribute to apoptosis through down-regulation of the p-Akt and PKA-PLK1 pathways. 15d-PGJ2 is a potential therapeutic agent for OS, exerting cytotoxicity mediated through both AKT and PKA-PLK1 inhibition, and these results form the basis for further analysis of its role in animal studies and clinical applications.
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Hole injection and electron overflow improvement in InGaN/GaN light-emitting diodes by a tapered AlGaN electron blocking layer.
Opt Express
PUBLISHED: 02-12-2014
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A tapered AlGaN electron blocking layer with step-graded aluminum composition is analyzed in nitride-based blue light-emitting diode (LED) numerically and experimentally. The energy band diagrams, electrostatic fields, carrier concentration, electron current density profiles, and hole transmitting probability are investigated. The simulation results demonstrated that such tapered structure can effectively enhance the hole injection efficiency as well as the electron confinement. Consequently, the LED with a tapered EBL grown by metal-organic chemical vapor deposition exhibits reduced efficiency droop behavior of 29% as compared with 44% for original LED, which reflects the improvement in hole injection and electron overflow in our design.
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Nonpalpable intramuscular hemangioma treated with hookwire localization and excision.
J Chin Med Assoc
PUBLISHED: 02-05-2014
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The local recurrence rate after surgical excision of intramuscular hemangioma reported is between 18% and 61%. The aim of this study was to review the clinical outcome and local recurrence rate after surgical excision of nonpalpable intramuscular hemangioma using preoperative ultrasound-guided hookwire localization.
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Effects of Danshensu and Salvianolic Acid B from Salvia miltiorrhiza Bunge (Lamiaceae) on cell proliferation and collagen and melanin production.
Molecules
PUBLISHED: 02-01-2014
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Danshensu (DSU) and salvianolic acid B (SAB) are the primary water-soluble compounds of Salvia miltiorrhiza Bunge (Lamiaceae). In this study, we analyzed the effects of DSU, SAB and a S. miltiorrhiza extract (SME) on cell proliferation. Additionally, the effects of DSU and SAB on collagen synthesis in Detroit 551 human normal fibroblast cells and on melanin production in B16 melanoma cells were verified. The results demonstrated that SME can enhance the proliferation of Detroit 551 cells and that this boost may be caused by DSU and SAB. This research showed that SME, DSU and SAB all have the ability to increase the production of collagen in Detroit 551 cells. The results also confirmed that DSU and SAB can attenuate the ?-MSH-stimulated melanin production of B16 cells by inhibiting tyrosinase activity. Therefore, SME, DSU and SAB each have the potential to be utilized as active ingredients in wound healing or cosmetic treatments. In the future, DSU and SAB could also be used as functional components for treating hyperpigmentation.
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Mortality and complications of hip fracture in young adults: a nationwide population-based cohort study.
BMC Musculoskelet Disord
PUBLISHED: 01-27-2014
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This study assessed the mortality and complications of hip fractures using in-patients aged 20-40 years from a nationwide population database in Taiwan.
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Gallic Acid Exhibits Risks of Inducing Muscular Hemorrhagic Liposis and Cerebral Hemorrhage-Its Action Mechanism and Preventive Strategy.
Phytother Res
PUBLISHED: 01-18-2014
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Gallic acid (3,4,5-trihydroxybenzoic acid) (GA) occurs in many plants. The adverse effects of GA are seldom cited. GA (6-14??M) provoked the hemorrhagic liposis of the cervical muscles and intracranial hemorrhage. The cause of these pathological events and the method for prevention are still lacking. Using the chicken embryo model and some selected nutraceutics such as folate, glutathione (GSH), N-acetylcysteine, and vitamin E (Vit E), we carried out this study. Results revealed that the action mechanism of GA involved (i) inducing hypoxia with upregulated gene hif-1? and downregulated ratio vegf-r2/vegf-a, leading to dys-vascularization and myopathy; (ii) impairing cytochrome c oxidase; (iii) stimulating creatine kinase and lactate dehydrogenase release; (iv) eliciting carnitine accumulation and liposis via downregulating gene CPT1; (v) suppressing superoxide dismutase and stimulating NO, H2 O2 , and malondialdehyde; and (vi) depleting erythrocytic and tissue GSH, resulting in hemorrhage. When both Vit E and GSH were applied to the day?1 chicks, a better alleviation effect was revealed. Conclusively, GA potentially exhibits adverse effect by eliciting hemorrhagic liposis of cervical muscles and cerebral hemorrhage. Supplementation with GSH, Vit E, and N-acetylcysteine is able to ameliorate these adverse effects, warranting the importance of restricting the clinical phytotherapeutic doses of GA and related compounds. Copyright © 2014 John Wiley & Sons, Ltd.
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Population-based epidemiology of postoperative venous thromboembolism in Taiwanese patients receiving hip or knee arthroplasty without pharmacological thromboprophylaxis.
Thromb. Res.
PUBLISHED: 01-14-2014
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Population-based evaluation on the incidence of postoperative venous thromboembolism (VTE) has not yet been reported for Asians receiving arthroplasty. In Taiwan, thromboprophylaxis was not commonly applied for patients. The population-based cohort study aimed to investigate the epidemiology, and to determine the risk factors VTE for patients receiving hip or knee replacement without pharmacological thromboprophylaxis in Taiwan.
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Hispolon decreases melanin production and induces apoptosis in melanoma cells through the downregulation of tyrosinase and microphthalmia-associated transcription factor (MITF) expressions and the activation of caspase-3, -8 and -9.
Int J Mol Sci
PUBLISHED: 01-08-2014
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Hispolon is one of the most important functional compounds that forms Phellinus linteus (Berkeley & Curtis) Teng. Hispolon has antioxidant, anti-inflammatory, antiproliferative and anticancer effects. In this study, we analyzed the functions of hispolon on melanogenesis and apoptosis in B16-F10 melanoma cells. The results demonstrated that hispolon is not an enzymatic inhibitor for tyrosinase; rather, it represses the expression of tyrosinase and the microphthalmia-associated transcription factor (MITF) to reduce the production of melanin in ?-melanocyte-stimulating hormone (?-MSH)-stimulated B16-F10 cells at lower concentrations (less than 2 ?M). In contrast, at higher concentration (greater than 10 ?M), hispolon can induce activity of caspase-3, -8 and -9 to trigger apoptosis of B16-F10 cells but not of Detroit 551 normal fibroblast cells. Therefore, we suggest that hispolon has the potential to treat hyperpigmentation diseases and melanoma skin cancer in the future.
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Effects of the novel poly(methyl methacrylate) (PMMA)-encapsulated organic ultraviolet (UV) filters on the UV absorbance and in vitro sun protection factor (SPF).
J. Photochem. Photobiol. B, Biol.
PUBLISHED: 01-07-2014
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Sunscreens are thought to protect skin from many of the harmful effects of ultraviolet (UV) light and the photostability of sunscreens is thus an important concern in their application. Therefore, to discover new UV filters or to modify well-known UV filters are presents an important way for development of sunscreens. In this study, we presented several novel poly(methyl methacrylate) (PMMA) encapsulated organic UV filters, including encapsulated benzophenone-3 (TB-MS), avobenzone (TA-MS), octyl methoxycinnamate (TO-MS) and diethylamino hydroxybenzoyl hexyl benzoate (TD-MS). Our results have demonstrated that PMMA-encapsulated UV filters have improved safety, photoprotective ability and photostability. We proposed therefore that these PMMA-encapsulated UV filters can be used as ingredients for sunscreen products in the future.
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Association of Brain-Derived Neurotrophic Factor Gene Val66Met Polymorphism with Primary Dysmenorrhea.
PLoS ONE
PUBLISHED: 01-01-2014
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Primary dysmenorrhea (PDM), the most prevalent menstrual cycle-related problem in women of reproductive age, is associated with negative moods. Whether the menstrual pain and negative moods have a genetic basis remains unknown. Brain-derived neurotrophic factor (BDNF) plays a key role in the production of central sensitization and contributes to chronic pain conditions. BDNF has also been implicated in stress-related mood disorders. We screened and genotyped the BDNF Val66Met polymorphism (rs6265) in 99 Taiwanese (Asian) PDMs (20-30 years old) and 101 age-matched healthy female controls. We found that there was a significantly higher frequency of the Met allele of the BDNF Val66Met polymorphism in the PDM group. Furthermore, BDNF Met/Met homozygosity had a significantly stronger association with PDM compared with Val carrier status. Subsequent behavioral/hormonal assessments of sub-groups (PDMs?=?78, controls?=?81; eligible for longitudinal multimodal neuroimaging battery studies) revealed that the BDNF Met/Met homozygous PDMs exhibited a higher menstrual pain score (sensory dimension) and a more anxious mood than the Val carrier PDMs during the menstrual phase. Although preliminary, our study suggests that the BDNF Val66Met polymorphism is associated with PDM in Taiwanese (Asian) people, and BDNF Met/Met homozygosity may be associated with an increased risk of PDM. Our data also suggest the BDNF Val66Met polymorphism as a possible regulator of menstrual pain and pain-related emotions in PDM. Absence of thermal hypersensitivity may connote an ethnic attribution. The presentation of our findings calls for further genetic and neuroscientific investigations of PDM.
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Manipulation therapy prior to diagnosis induced primary osteosarcoma metastasis--from clinical to basic research.
PLoS ONE
PUBLISHED: 01-01-2014
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Osteosarcoma (OS) patients who suffer manipulation therapy (MT) prior to diagnosis resulted in poor prognosis with increasing metastasis or recurrence rate. The aim of the study is to establish an in vivo model to identify the effects of MT on OS. The enrolled 235 OS patients were followed up in this study. In vivo nude mice model with tibia injection of GFP-labeled human OS cells were randomly allocated into MT(+) that with repeated massage on tumor site twice a week and no treatment as MT(-) group. The five-year survival, metastasis and recurrence rates were recorded in clinical subjects. X-ray plainfilm, micro-PET/CT scan, histopathology, serum metalloproteinase 2 (MMP2), metalloproteinase 9 (MMP9) level and human kinase domain insert receptor (KDR) pattern were assayed in mice model. The results showed that patient with MT decreased 5-year survival and higher recurrence or metastasis rate. Compatible with clinical findings, the decreased body weight (30.5 ± 0.65 g) and an increased tumor volume (8.3 ± 1.18 mm3) in MT(+) mice were observed. The increasing signal intensity over lymph node region of hind limb by micro-PET/CT and the tumor cells were detected in lung and bilateral lymph nodes only in MT(+) group. MMP2 (214 ± 9.8 ng/ml) and MMP9 (25.5 ± 1.81 ng/ml) were higher in MT(+) group than in MT(-) group (165 ± 7.8 ng/ml and 16.9 ± 1.40 ng/ml, individually) as well as KDR expression. Taking clinical observations and in vivo evidence together, MT treatment leads to poor prognosis of primary osteosarcoma; physicians should pay more attention on patients who seek MT before diagnosis.
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Effect of Vetiveria zizanioides essential oil on melanogenesis in melanoma cells: downregulation of tyrosinase expression and suppression of oxidative stress.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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The major objective of this study was to estimate the hypopigmentation function of the essential oil from Vetiveria zizanioides (VZ-EO). Our results indicated that VZ-EO exhibits potent lipid peroxidation inhibitory activity to moderate the bleaching of ?-carotene and to maintain the cellular glutathione (GSH) levels. VZ-EO can markedly decrease melanin production and tyrosinase activity in ?-melanin-stimulating-hormone- (?-MSH-) stimulated B16 cells. The effect of VZ-EO on melanogenesis is achieved by the suppression of cellular tyrosinase expression. The results demonstrated that the activity of VZ-EO on melanogenesis might be the result of its potent antioxidative ability, which was reflected in the decreased cellular oxidant and malondialdehyde (MDA) levels and the recovered activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) in ?-MSH-stimulated B16 cells. The most abundant compound in VZ-EO is cedr-8-en-13-ol (12.4%), which has a strong capability to inhibit lipid peroxidation. Therefore, VZ-EO has the potential to become an ingredient in future hypopigmentation drugs, foods, and cosmetics.
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The melanogenesis alteration effects of Achillea millefolium L. essential oil and linalyl acetate: involvement of oxidative stress and the JNK and ERK signaling pathways in melanoma cells.
PLoS ONE
PUBLISHED: 01-01-2014
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The mitogen-activated protein kinase (MAPK) family, including extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK)1/2 and p38 MAPK, is known to be activated by ultraviolet (UV) radiation in melanocytes to regulate melanin production. Reactive oxygen species (ROS) play important roles in the pathway of ERK and JNK activation. It has been established that the essential oil of Achillea millefolium L. (AM-EO) has activities that suppress the oxidative stress and inflammatory responses. Thus, we analyzed the effects of AM-EO on melanogenesis in melanocyte stimulating hormone (?-MSH) treated melanoma cells. The results demonstrated that AM-EO suppresses melanin production by decreasing tyrosinase activity through the regulation of the JNK and ERK signaling pathways. This effect might be associated with the AM-EO activity leading to the suppression of ROS, and linalyl acetate is its major functional component. Therefore, we propose that AM-EO has the potential to treat hyperpigmentation in the future.
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Biomechanical comparison of the K-ROD and Dynesys dynamic spinal fixator systems - a finite element analysis.
Biomed Mater Eng
PUBLISHED: 10-30-2013
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Dynamic spinal fixators, such as the Dynesys (DY) and K-ROD (KD) systems, are designed to restore spinal stability and to provide flexibility. The long-term complications of implant breakage and the biomechanics of the adjacent and the bridged levels using the KD system are still unknown. Therefore, this study aims to investigate and compare the biomechanical effects of the KD system and the DY system. Finite element (FE) models of the degenerated lumbar spine, the DY system, and the KD system were each reconstructed. Hybrid-controlled analysis was applied in the three FE models. The FE results indicated that the KD system supplies the most stiffness during extension and the least stiffness during flexion, in contrast to the DY system. In contrast to the DY system, the KD system increased the facet contact force of the adjacent level, but this system decreased the screw stress on the cranial adjacent disc and the pedicle during flexion.
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Quantitative assessment of cerebral glucose metabolic rates after blood-brain barrier disruption induced by focused ultrasound using FDG-MicroPET.
Neuroimage
PUBLISHED: 10-11-2013
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The goal of this study was to evaluate the pharmacokinetics of (18)F-2-fluoro-2-deoxy-d-glucose ((18)F-FDG) and the expression of glucose transporter 1 (GLUT1) protein after blood-brain barrier (BBB) disruption of normal rat brains by focused ultrasound (FUS). After delivery of an intravenous bolus of ~37MBq (1mCi) (18)F-FDG, dynamic positron emission tomography scans were performed on rats with normal brains and those whose BBBs had been disrupted by FUS. Arterial blood sampling was collected throughout the scanning procedure. A 2-tissue compartmental model was used to estimate (18)F-FDG kinetic parameters in brain tissues. The rate constants Ki, K1, and k3 were assumed to characterize the uptake, transport, and hexokinase activity, respectively, of (18)F-FDG. The uptake of (18)F-FDG in brains significantly decreased immediately after the blood-brain barrier was disrupted. At the same time, the derived values of Ki, K1, and k3 for the sonicated brains were significantly lower than those for the control brains. In agreement with the reduction in glucose, Western blot analyses confirmed that focused ultrasound exposure significantly reduced the expression of GLUT1 protein in the brains. Furthermore, the effect of focused ultrasound on glucose uptake was transient and reversible 24h after sonication. Our results indicate that focused ultrasound may inhibit GLUT1 expression to decrease the glucose uptake in brain tissue during the period of BBB disruption.
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The metal grating design of plasmonic hybrid III-V/Si evanescent lasers.
Opt Express
PUBLISHED: 10-10-2013
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A hybrid III-V/silicon laser design with a metal grating layer inserted in between is proposed and numerically studied. The metal grating layer is buried in a silicon ridge waveguide surrounded by silicon dioxide, and its structural parameters such as periodicity, width and depth can be varied for optimization purpose. The plasmonic effect originated from the grating layer can manage optical fields between III-V and silicon layers in hopes of dimension reduction. The substrate is planarized to minimize the bonding failure. A numerical algorithm with various combinations of metal grating and waveguide structural parameters was created and the optimal design with 730 nm grating period and 600 nm of buried waveguide ridge height was obtained by minimizing the corresponding laser threshold. With top AlInGaAs quantum wells and optimized design of hybrid metal/silicon waveguide, a 0.6 ?m(-1) threshold gain can be achieved.
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Effects of mosapride on secondary peristalsis in patients with ineffective esophageal motility.
Scand. J. Gastroenterol.
PUBLISHED: 10-08-2013
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Abstract Objective. Ineffective esophageal motility is frequently found in patients with gastroesophageal reflux diseases. Secondary peristalsis contributes to esophageal acid clearance. Mosapride improves gastrointestinal (GI) motility by acting on 5-hydroxytrypatamine4 receptors. The authors aimed to evaluate the effect of mosapride on secondary peristalsis in patients with ineffective esophageal motility. Material and methods. After recording primary peristalsis baseline, secondary peristalsis was stimulated by slowly and rapidly injecting mid-esophageal air in 18 patients. Two separate experiments were randomly performed with 40 mg oral mosapride or placebo. Results. Mosapride had no effect on the threshold volume of secondary peristalsis during slow air distension (9.8 ± 0.97 vs. 10.2 ± 1.0 mL; p = 0.84), but decreased the threshold volume during rapid air distension (4.1 ± 0.2 vs. 4.6 ± 0.3 mL; p = 0.001). The efficiency of secondary peristalsis during rapid air distension increased with mosapride (70% [40-95%]) compared with placebo (60% [10-85%]; p = 0.0003). Mosapride had no effect on the amplitudes of distal pressure wave of secondary peristalsis during slow (94.3 ± 9 vs. 101.9 ± 9.1 mmHg; p = 0.63) or rapid air distension (89.3 ± 9 vs. 95.2 ± 8.3 mmHg; p = 0.24). Conclusions. Mosapride improves esophageal sensitivity of secondary peristalsis by abrupt air distension but has limited effect on the motor properties of secondary peristalsis in ineffective esophageal motility patients. Despite its well-known prokinetic effect, mosapride enhances the efficiency of secondary peristalsis in patients with ineffective esophageal motility through augmenting esophageal sensitivity instead of motility.
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Modulation of CEST images in vivo by T1 relaxation: a new approach in the design of responsive PARACEST agents.
J. Am. Chem. Soc.
PUBLISHED: 09-25-2013
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A novel approach for the design of responsive paramagnetic chemical exchange saturation transfer (PARACEST) magnetic resonance imaging (MRI) agents has been developed where the signal is "turned on" by altering the longitudinal relaxation time (T1) of bulk water protons. To demonstrate this approach, a model Eu(DOTA-tetraamide) complex (DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) containing two nitroxide free radical units was synthesized. The nitroxide groups substantially shortened the T1 of the bulk water protons which, in turn, resulted in quenching of the CEST signal. Reduction of paramagnetic nitroxide moieties to a diamagnetic species resulted in the appearance of CEST. The modulation of CEST by T1 relaxation provides a new platform for designing biologically responsive MRI agents.
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Multiple models of porcine teschovirus pathogenesis in endemically infected pigs.
Vet. Microbiol.
PUBLISHED: 09-02-2013
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Porcine teschoviruses (PTVs) belong to the genus Teschovirus within the family Picornaviridae. PTVs are universal contaminants in pig herds in endemic and multi-infection status. To further the understanding of PTV pathogenesis in endemically infected pigs, a set of samples was studied by real time reverse transcription PCR (qRT-PCR) to quantitate viral loads in tissues and by in situ hybridization (ISH) to locate PTV signals in target cells, both targeting the 5-NTR. cRNA of PTV-1 and PTV-7, in vitro transcribed from cloned fragments of 5-NTR of 2 viruses, was used to construct standard curves and to run parallel in qRT-PCR, which had detection limits of 10(1) copies/per reaction, with a linearity in between 10(1) and 10(7) copies/per reaction and correlation coefficients of 0.997-0.9988. The qRT-PCR specifically amplified RNA from PTV-1 to -11, while excluding those of Sapelovirus, PEV-9 and PEV-10. Inguinal lymph node (LN) had the highest viral load of all (assuming 100%), followed by ileac LN (89-91%), tonsil (66-68%), ileum (59-60%), spleen (38-40%), and kidney (30-31%), with the least in brain (22.9%) of the inguinal LN. The 22.9% load in brain was higher than that anticipated from a simple fecal-oral-viremia operative model. The results suggested in addition that intranasal infection and retrograding axonal infection from the tonsils were equally operative and significant. ISH revealed PTV signals in a wider variety of tissue cell types than before. PTV signals were noted most impressively in neurons of the cerebral cortex and hippocampus and in the dark zone of the germinal center and adjacent paracortex of regional LN. Multiple operative models indicated that PTVs seemed to have no difficulty invading the brain. The key to whether encephalitis would ensue resided in the animals immune status and topographic differences of neurons susceptibilities to PTVs. When common co-infected agents are present, as is typical in the field, PTVs may synergize in causing diseases.
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Thrombolytic Therapy Is an Only Determinant Factor for Stroke Evolution in Large Anterior Choroidal Artery Infarcts.
J Stroke Cerebrovasc Dis
PUBLISHED: 08-14-2013
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Large anterior choroidal artery (AChA) infarcts are frequently associated with stroke evolution. This study aimed to investigate the major determinants for stroke evolution in patients with large AChA infarcts.
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Osteomyelitis of the femur mimicking bone tumors: a review of 10 cases.
World J Surg Oncol
PUBLISHED: 07-27-2013
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The clinical symptoms and radiographic appearance of osteomyelitis can mimic those of bone tumors.
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Polymethylmethacrylate augmentation of cannulated pedicle screws for fixation in osteoporotic spines and comparison of its clinical results and biomechanical characteristics with the needle injection method.
J Spinal Disord Tech
PUBLISHED: 07-27-2013
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This is a retrospective study carried out to evaluate the clinical results of patients with osteoporosis and various spinal diseases treated surgically with polymethylmethacrylate (PMMA)-augmented cannulated pedicle screws, and to compare this method with the needle injection technique in terms of the clinical results and fixation strength.
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Probiotic-fermented purple sweet potato yogurt activates compensatory IGF?IR/PI3K/Akt survival pathways and attenuates cardiac apoptosis in the hearts of spontaneously hypertensive rats.
Int. J. Mol. Med.
PUBLISHED: 07-09-2013
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Apoptosis is recognized as a predictor of adverse outcomes in subjects with cardiac diseases. The aim of this study was to explore the effects of probiotic-fermented purple sweet potato yogurt (PSPY) with high ?-aminobutyric acid (GABA) content on cardiac apoptosis in spontaneously hypertensive rat (SHR) hearts. The rats were orally adminsitered with 2 different concentrations of PSPY (10 and 100%) or captopril, 15.6 mg/kg, body weight (BW)/day. The control group was administered distilled water. DAPI and TUNEL staining were used to detect the numbers of apoptotic cells. A decrease in the number of TUNEL-positive cardiac myocytes was observed in the SHR-PSPY (10 and 100%) groups. In addition, the levels of key components of the Fas receptor- and mitochondrial-dependent apoptotic pathways were determined by western blot analysis. The results revealed that the levels of the key components of the Fas receptor- and mitochondrial-dependent apoptotic pathway were significantly decreased in the SHR-captopril, and 10 and 100% PSPY groups. Additionally, the levels of phosphorylated insulin-like growth factor?I receptor (p-IGF?IR) were increased in SHR hearts from the SHR-control group; however, no recovery in the levels of downstream signaling components was observed. In addition, the levels of components of the compensatory IGF-IR-dependent survival pathway (p-PI3K and p-Akt) were all highly enhanced in the left ventricles in the hearts form the SHR-10 and 100% PSPY groups. Therefore, the oral administration of PSPY may attenuate cardiomyocyte apoptosis in SHR hearts by activating IGF?IR-dependent survival signaling pathways.
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The novel synthetic compound 6-acetyl-9-(3,4,5-trimetho-xybenzyl)-9H-pyrido[2,3-b]indole induces mitotic arrest and apoptosis in human COLO 205 cells.
Int. J. Oncol.
PUBLISHED: 07-05-2013
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A novel synthetic compound 6-acetyl-9-(3,4,5-trimetho-xybenzyl)-9H-pyrido[2,3-b]indole (HAC-Y6) demonstrated selective anticancer activity. In the present study, COLO 205 cells were treated with HAC-Y6 to investigate the molecular mechanisms underlying its effects. HAC-Y6 induced growth inhibition, G2/M arrest and apoptosis in COLO 205 cells with an IC50 of 0.52±0.035 µM. Annexin V/PI double staining demonstrated the presence of apoptotic cells. JC-1 staining analysis showed that HAC-Y6 decreased mitochondrial membrane potential in support of apoptosis. An immunostaining assay revealed that HAC-Y6 depolymerized microtubules. Treatment of COLO 205 cells with HAC-Y6 resulted in increased expression of BubR1 and cyclin B1 and decreased expression of aurora A, phospho-aurora A, aurora B, phospho-aurora B and phospho-H3. HAC-Y6 treatment increased protein levels of active caspase-3, caspase-9, Endo G, AIF, Apaf-1, cytochrome c and Bax, but treatment with the compound caused reduced levels of procaspase-3, procaspase-9, Bcl-xL and Bcl-2. Overall, our results suggest that HAC-Y6 exerts anticancer effects by disrupting microtubule assembly and inducing G2/M arrest, polyploidy and apoptosis via mitochondrial pathways in COLO 205 cells.
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Progressive growth of arachnoid cysts with cauda equina syndrome after lumbar spine surgery.
J Chin Med Assoc
PUBLISHED: 06-25-2013
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Intradural arachnoid cysts are a rare cause of spinal cord compression. In symptomatic cases neuropathic pain, gait disturbance, and paraparesis or quadriparesis are often present. Postoperative arachnoid cysts have rarely been reported. We describe a 56-year-old male who developed progressively enlarging arachnoid cysts with cauda equina syndrome and vertebral body erosion after lumbar surgery. The clinical presentation of the patient, the possible mechanisms of cyst formation, and the management of the disease are discussed with regard to previous literature.
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Pulmonary embolism following total knee arthroplasty in Taiwanese patients.
J Chin Med Assoc
PUBLISHED: 06-24-2013
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Pulmonary embolism is a relatively uncommon, but serious, postoperative complication of hip and knee arthroplasty; however, little information is available about the prevalence of pulmonary embolism in Taiwan.
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Synthesis and bioactivity of ?-(1?4)-linked oligomannoses and partially acetylated derivatives.
J. Org. Chem.
PUBLISHED: 06-18-2013
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The synthesis of ?-(1?4)-linked hexa- to octamannoses and their partially acetylated derivatives was efficiently carried out by assembly of appropriate oligomeric fragments using ?-selective glucosylation followed by gluco to manno epimerization at a late stage of the synthetic pathway. In the course of this study, we also observed that 2-O-acetylated oligomannoses coexisted in equilibrium with the 3-O-acetylated isomers due to intramolecular migration of the acetyl group. Bioactivity of the synthetic oligomannoses and partially acetylated derivatives was investigated in order to identify the possible smallest oligomer for induction of cytokines as that shown in the polysaccharides extracted from Dendrobium huoshanense.
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Effects of cord pretension and stiffness of the Dynesys system spacer on the biomechanics of spinal decompression- a finite element study.
BMC Musculoskelet Disord
PUBLISHED: 06-14-2013
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The Dynesys system provides stability for destabilized spines while preserving segmental motion. However, clinical studies have demonstrated that the Dynesys system does not prevent adjacent segment disease. Moreover, biomechanical studies have revealed that the stiffness of the Dynesys system is comparable to rigid fixation. Our previous studies showed that adjusting the cord pretension of the Dynesys system alleviates stress on the adjacent level during flexion. We also demonstrated that altering the stiffness of Dynesys system spacers can alleviate stress on the adjacent level during extension of the intact spine. In the present study, we hypothesized that omitting the cord preload and changing the stiffness of the Dynesys system spacers would abate stress shielding on adjacent spinal segments.
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Concomitant tibial shaft and posterior malleolar fractures can be readily diagnosed from plain radiographs: A retrospective study.
J Chin Med Assoc
PUBLISHED: 06-07-2013
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Concomitant tibial shaft and posterior malleolar fractures (PMFs) are often encountered in clinical settings. Plain films were reviewed for concomitant PMF, and fracture patterns were analyzed by focusing on the integrity of the fibula and the location of the fibular fracture.
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Primary cervical osteomyelitis.
J Chin Med Assoc
PUBLISHED: 05-20-2013
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Cervical osteomyelitis accounts for only 3-11% of all cases of spinal osteomyelitis, and the diagnosis may be delayed. The characteristics of different pathogens causing cervical osteomyelitis are not fully understood, and there are few established guidelines for treatment.
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Neurovascular abnormalities in humans and mice with Huntingtons disease.
Exp. Neurol.
PUBLISHED: 05-11-2013
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Cerebral microvascular aberrations have recently become recognized as a source of pathologies in neurodegenerative disorders, but this concept has not been fully examined with respect to Huntingtons disease (HD). A novel in vivo technique, three-dimensional microscopic magnetic resonance angiography (?MRA), allows visualization of the neurovascular system in exquisite detail and provides quantitative structural and functional information. This technique was applied in the present study, in parallel with immunohistological analysis and behavioral assessment, to a well-characterized mouse model of HD (R6/2). Dynamic contrast-enhanced magnetic resonance imaging was used to examine the integrity of the blood-brain barrier (BBB). The ?MRA findings revealed an increase in vessel volume fraction and cerebral blood volume in the brains of R6/2 mice at the age of 7weeks when no apparent motor dysfunction was detected. Collagen IV immunostaining disclosed an enhancement in vessel density, but not in vessel size of the microvasculature in the mouse HD brain. This change in neurovasculature worsened with disease progression, with no apparent disruption in the BBB. Most importantly, immunohistological assays of human tissues revealed that the vessel densities in the cortex, caudate/putamen, and substantia nigra were higher in HD patients than in non-HD human subjects. The early onset of such vessel aberrations could be used as a biomarker for the early diagnosis of HD.
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Suppression of TLR-4-Related Inflammatory Pathway and Anti-Fibrosis Effects of Probiotic-Fermented Purple Sweet Potato Yogurt in Hearts of Spontaneously Hypertensive Rats.
Chin J Physiol
PUBLISHED: 05-10-2013
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Inflammation plays an important role in triggering fibrosis of cardiovascular disease and hypertension. Gamma aminobutyric acid (GABA) has hypotensive effect; GABA concentration could be enhanced in milk fermented with lactic acid bacteria (LAB). This study evaluated the effect of probiotic-fermented purple sweet potato yogurt (PSPY) on the toll-like receptor 4 (TLR-4)-related inflammatory components, and on fibrosis in the heart of spontaneously hypertensive rat (SHR). TLR4- related pathway and fibrosis-associated proteins TGF? and FGF2 were significantly increased in SHR hearts, but were highly suppressed in 10% PSPY-fed rats. Microscopic examination with Masson trichrome staining of left ventricle further demonstrated that 10% and 100% PSPY both significantly reduced interstitial fibrosis in SHR hearts. These findings indicated that oral administration of 10% probiotic-fermented PSPY was strong enough to lower cardiac fibrosis in SHR rats through the suppression of TLR-4-related inflammatory pathway. Therefore, PSPY may be included in diets to help prevent cardiac fibrosis in patients with hypertension.
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Design and synthesis of 6,7-methylenedioxy-4-substituted phenylquinolin-2(1H)-one derivatives as novel anticancer agents that induce apoptosis with cell cycle arrest at G2/M phase.
Bioorg. Med. Chem.
PUBLISHED: 05-09-2013
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Novel 6,7-methylenedioxy-4-substituted phenylquinolin-2(1H)-one derivatives 12a-n were designed and prepared through an intramolecular cyclization reaction and evaluated for in vitro anticancer activity. Among the synthesized compounds, 6,7-methylenedioxy-4-(2,4-dimethoxyphenyl)quinolin-2(1H)-one (12e) displayed potent cytotoxicity against several different tumor cell lines at a sub-micromolar level. Furthermore, results of fluorescence-activated cell sorting (FACS) analysis suggested that 12e induced cell cycle arrest in the G2/M phase accompanied by apoptosis in HL-60 and H460 cells. This action was confirmed by Hoechst staining and caspase-3 activation. Due to their easy synthesis and remarkable biological activities, 4-phenylquinolin-2(1H)-one analogs (4-PQs) are promising new anticancer leads based on the quinoline scaffold. Accordingly, compound 12e was identified as a new lead compound that merits further optimization and development as an anticancer candidate.
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Comparative study on the photostability of arbutin and deoxy arbutin: sensitivity to ultraviolet radiation and enhanced photostability by the water-soluble sunscreen, benzophenone-4.
Biosci. Biotechnol. Biochem.
PUBLISHED: 05-07-2013
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Arbutin and deoxy arbutin may release hydroquinone under some conditions. We therefore investigated the photostability of arbutin and deoxy arbutin in an aqueous solution. The results revealed arbutin and deoxy arbutin to be photolabile in an aqueous solution. Deoxy arbutin was less stable than arbutin when exposed to UV radiation. The hydroquinone concentration was also increased during the radiation period in both solutions. Benzophenone-4 could clearly improve the photostability of arbutin during the period of UV radiation, but only slightly enhance the photostability of deoxy arbutin.
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Association of Egr-1 and autophagy-related gene polymorphism in men with chronic obstructive pulmonary disease.
J. Formos. Med. Assoc.
PUBLISHED: 04-28-2013
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Autophagy is important in cellular homeostasis and control of inflammatory immune response. Increased autophagy has recently been associated with increased cell death and chronic obstructive pulmonary disease (COPD) pathogenesis. Two autophagy regulator genes have been identified: Egr-1 (early growth response), associated with different phenotype expressions in asthma; and, Atg16L1 (autophagy related 16-like 1), a candidate gene responsible for susceptibility to chronic inflammatory diseases. We will explore the role of the Egr-1 and Atg16L1 gene polymorphisms in COPD.
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Prevalence of Gastroesophageal Reflux Disease in Major Depressive Disorder: A Population-Based Study.
Psychosomatics
PUBLISHED: 04-27-2013
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Gastroesophageal reflux disease (GERD) is a common physical disease among psychiatric patients. We conducted this study to investigate the prevalence and risk of GERD in patients with major depressive disorder (MDD) in Taiwan.
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Surgical treatment for septic arthritis of the knee joint in elderly patients: a 10-year retrospective clinical study.
Orthopedics
PUBLISHED: 04-18-2013
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Septic arthritis is the most rapidly destructive joint disease, but its early diagnosis remains challenging; delayed or inadequate treatment, even by expert physicians, can lead to irreversible joint destruction. Between 25% and 50% of patients develop irreversible loss of joint function, which is especially concerning in elderly patients. To understand the factors influencing the outcome of septic arthritis, the authors reviewed patients aged older than 50 years who had undergone debridement surgery for primary septic arthritis at their institution between 1998 and 2008. Ninety-two patients (92 knees) were enrolled in the study; 14 did not meet inclusion criteria and were excluded from the final analysis. Of the 78 included patients, 7 underwent arthrodesis, 22 underwent total knee arthroplasty, 19 were indicated for total knee arthroplasty for severe knee joint osteoarthritis but did not undergo surgery by the end of this study, and the remaining 30 had no or mild symptoms of osteoarthrosis and did not receive any surgical procedure. Staphylococcus aureus was the most common pathogenic agent (38%), followed by mixed bacterial infection (10%). Several factors negatively influenced the final clinical outcome, including delayed treatment, advanced macroscopic staging made during debridement surgery, performing multiple debridement surgeries, and a larger Lysholm score difference pre- and posttreatment. More antibiotics administered, longer duration of antibiotic treatment, and more pathogenic agents present were also significantly correlated with poor outcome. These findings shed new light on the management of septic arthritis. Accurate diagnoses and effective treatments are important for the clinical outcome of knee joint bacterial infection in elderly patients.
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Optimization of Culture Conditions for Stem Cells Derived from Human Anterior Cruciate Ligament and Bone Marrow.
Cell Transplant
PUBLISHED: 04-12-2013
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Tissue engineering with stem cells is a fascinating approach for treating anterior cruciateligament (ACL) injuries. In our previous study, stem cells isolated from the human anteriorcruciate ligament were shown to possess extensive proliferation and differentiationcapabilities when treated with specific growth factors. However, optimal culture conditionsand the usefulness of fetal bovine serum (FBS) as a growth factor in in vitro culture systemsare yet to be determined. In this study, we compared the effects of different culture mediacontaining combinations of various concentrations of FBS and the growth factors basicfibroblastic growth factor (bFGF) and transforming growth factor ?1 (TGF- ?1) on theproliferation and differentiation of ligament-derived stem cells (LSCs) and bone marrowmesenchymal stem cells (BMSCs). We found that ?-MEM plus 10% FBS and bFGF was ableto maintain both LSCs and BMSCs in a relatively undifferentiated state but with lower majorextracellular matrix (ECM) component gene expression and protein production, which isbeneficial for stem cell expansion. However, the differentiation and proliferation potentials ofLSCs and BMSCs were increased when cultured in MesenPRO, a commercially availablestem cell medium containing 2% FBS. MesenPRO in conjunction with TGF- ?1 had thegreatest ability to induce the differentiation of BMSCs and LSCs to ligament fibroblasts,which was evidenced by the highest ligamentous ECM gene expression and proteinproduction. These results indicate that culture media and growth factors play a very importantrole in the success of tissue engineering. With ?-MEM plus 10% FBS and bFGF, rapidproliferation of stem cellscan be achieved. In this study, MesenPRO was able to promotedifferentiation of both LSCs and BMSCs to ligament fibroblasts. Differentiation was furtherincreased by TGF- ?1. With increasing understanding of the effects of different culture mediaand growth factors, manipulation of stem cells in the desired direction for ligament tissueengineering can be achieved.
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Metformin enhances cisplatin cytotoxicity by suppressing signal transducer and activator of transcription-3 activity independently of the liver kinase B1-AMP-activated protein kinase pathway.
Am. J. Respir. Cell Mol. Biol.
PUBLISHED: 03-26-2013
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Metformin has been used as first-line treatment in patients with type 2 diabetes, and is reported to reduce cancer risk and progression by activating the liver kinase B1 (LKB1)-AMP-activated protein kinase (AMPK) pathway. Cisplatin remains the main drug for treating advanced non-small-cell lung cancer. However, drug resistance often develops through several mechanisms during the treatment course, including one mechanism mediated by the activation of the IL-6/signal transducer and activator of transcription (STAT)-3 pathway, related to the generation of reactive oxygen species (ROS). This study demonstrated a correlation between STAT3 phosphorylation and cisplatin cytotoxicity, using AS2 (PC14PE6/AS2)-derived cell lines (AS2/S3C) that contained constitutively active STAT3 plasmids as a model. A STAT3 inhibitor (JSI-124) enhanced the cisplatin sensitivity in AS2 cells, whereas metformin inhibited STAT3 phosphorylation and enhanced cisplatin cytotoxicity. By contrast, another AMPK activator (5-aminoimidazole-4-carboxamide-riboside) failed to produce these effects. LKB1-AMPK silencing by small, interfering RNA or mammalian target of rapamycin (mTOR) inhibition by rapamycin or pp242 did not alter the effect of metformin on STAT3 activity suppression, suggesting that metformin can modulate the STAT3 pathway through an LKB1-AMPK-independent and probably mTOR-independent mechanism. Metformin also inhibited cisplatin-induced ROS production and autocrine IL-6 secretion in AS2 cells. Both mechanisms contributed to the ability of metformin to suppress STAT3 activation in cancer cells, which resulted in the decreased secretion of vascular endothelial growth factor by cancer cells. The growth of subcutaneous tumor xenografts was significantly delayed by a combination of cisplatin and metformin. This is the first study to demonstrate that metformin suppresses STAT3 activation via LKB1-AMPK-mTOR-independent but ROS-related and autocrine IL-6 production-related pathways. Thus, metformin helps to overcome tumor drug resistance by targeting STAT3.
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Achillea millefolium L. Essential Oil Inhibits LPS-Induced Oxidative Stress and Nitric Oxide Production in RAW 264.7 Macrophages.
Int J Mol Sci
PUBLISHED: 03-18-2013
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Achillea millefolium L. is a member of the Asteraceae family and has been used in folk medicine in many countries. In this study, 19 compounds in A. millefolium essential oil (AM-EO) have been identified; the major components are artemisia ketone (14.92%), camphor (11.64%), linalyl acetate (11.51%) and 1,8-cineole (10.15%). AM-EO can suppress the inflammatory responses of lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages, including decreased levels of cellular nitric oxide (NO) and superoxide anion production, lipid peroxidation and glutathione (GSH) concentration. This antioxidant activity is not a result of increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, but rather occurs as a result of the down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-? (TNF-?), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) expression, thus reducing the inflammatory response. Therefore, AM-EO can be utilized in many applications, including the treatment of inflammatory diseases in the future.
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High thermal stability of correlated color temperature using current compensation in hybrid warm white high-voltage LEDs.
Opt Express
PUBLISHED: 03-14-2013
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This study experimentally and numerically examines the correlated color temperature (CCT) stability issue for hybrid warm white high-voltage light-emitting diodes (HV-LEDs) by using a current compensation method. This method could efficiently maintain the CCT stability factor at approximately 1.0 and yield greater color uniformity with ?uv values ranging from 0.017 to 0.003 in CIE 1976 chromaticity coordinates. The simulation results show that the red chip intensity drop is the primary cause of CCT instability in the hybrid warm white system when the temperature increases. Therefore, Furthermore, results indicate that the relative lumen drop improves from 21% to 15% by using a current compensation method.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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