38 research outputs found

    Tumor necrosis factor-α enhances hyperbaric oxygen-induced visfatin expression via JNK pathway in human coronary arterial endothelial cells

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    <p>Abstract</p> <p>Background</p> <p>Visfatin, a adipocytokine with insulin-mimetic effect, plays a role in endothelial angiogenesis. Hyperbaric oxygen (HBO) has been used in medical practice. However, the molecular mechanism of beneficial effects of HBO is poorly understood. We sought to investigate the cellular and molecular mechanisms of regulation of visfatin by HBO in human coronary arterial endothelial cells (CAECs).</p> <p>Methods</p> <p>Human CAECs were exposed to 2.5 atmosphere absolute (ATA) of oxygen in a hyperbaric chamber. Western blot, real-time polymerase chain reaction, and promoter activity assay were performed. In vitro glucose uptake and tube formation was detected.</p> <p>Results</p> <p>Visfatin protein (2.55-fold) and mRNA (2.53-fold) expression were significantly increased after exposure to 2.5 ATA HBO for 4 to 6 h. Addition of SP600125 and JNK siRNA 30 min before HBO inhibited the induction of visfatin protein. HBO also significantly increased DNA-protein binding activity of AP-1 and visfatin promoter activity. Addition of SP600125 and TNF-α monoclonal antibody 30 min before HBO abolished the DNA-protein binding activity and visfatin promoter activity induced by HBO. HBO significantly increased secretion of TNF-α from cultured human CAECs. Exogenous addition of TNF-α significantly increased visfatin protein expression while TNF-α antibody and TNF-α receptor antibody blocked the induction of visfatin protein expression induced by HBO. HBO increased glucose uptake in human CAECs as HBO and visfatin siRNA and TNF-α antibody attenuated the glucose uptake induced by HBO. HBO significantly increased the tube formation of human CAECs while visfatin siRNA, TNF-α antibody inhibited the tube formation induced by HBO.</p> <p>Conclusions</p> <p>HBO activates visfatin expression in cultured human CAECs. HBO-induced visfatin is mediated by TNF-α and at least in part through JNK pathway.</p

    Customer Behavior Survery for Cultural and Creative Park in Taiwan

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    Cultural and Creative Park is a recreational campus which usually consists of exhibition, gallery, show room, movie theater, and multi-function facilities to provide the cultural activities. Besides, in the Cultural and Creative Park, restaurants, coffee shops, bookstores, gift shops, and other business units are nearby. How to improve the customer experience in the Cultural and Creative Park is an important research question for the managerial division to promote culture industries. In this research, the questionnaires were developed and performed in one of creative park in Taipei, Taiwan to study customer behavior. This paper addresses the survey result and the insights revealed from the survey

    Cancer effects of formaldehyde: a proposal for an indoor air guideline value

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    Formaldehyde is a ubiquitous indoor air pollutant that is classified as “Carcinogenic to humans (Group 1)” (IARC, Formaldehyde, 2-butoxyethanol and 1-tert-butoxypropanol-2-ol. IARC monographs on the evaluation of carcinogenic risks to humans, vol 88. World Health Organization, Lyon, pp 39–325, 2006). For nasal cancer in rats, the exposure–response relationship is highly non-linear, supporting a no-observed-adverse-effect level (NOAEL) that allows setting a guideline value. Epidemiological studies reported no increased incidence of nasopharyngeal cancer in humans below a mean level of 1 ppm and peak levels below 4 ppm, consistent with results from rat studies. Rat studies indicate that cytotoxicity-induced cell proliferation (NOAEL at 1 ppm) is a key mechanism in development of nasal cancer. However, the linear unit risk approach that is based on conservative (“worst-case”) considerations is also used for risk characterization of formaldehyde exposures. Lymphohematopoietic malignancies are not observed consistently in animal studies and if caused by formaldehyde in humans, they are high-dose phenomenons with non-linear exposure–response relationships. Apparently, these diseases are not reported in epidemiological studies at peak exposures below 2 ppm and average exposures below 0.5 ppm. At the similar airborne exposure levels in rodents, the nasal cancer effect is much more prominent than lymphohematopoietic malignancies. Thus, prevention of nasal cancer is considered to prevent lymphohematopoietic malignancies. Departing from the rat studies, the guideline value of the WHO (Air quality guidelines for Europe, 2nd edn. World Health Organization, Regional Office for Europe, Copenhagen, pp 87–91, 2000), 0.08 ppm (0.1 mg m−3) formaldehyde, is considered preventive of carcinogenic effects in compliance with epidemiological findings

    Biofabrication of gold nanoparticles by Shewanella species

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    Abstract Background Shewanella oneidensis MR-1 (MR-1) and Shewanella xiamenensis BC01 (SXM) are facultative anaerobic bacteria that exhibit outstanding performance in the dissimilatory reduction of metal ions. Shewanella species have been reported to produce metal nanoparticles, but the mechanism and optimization are still not extensively studied and clearly understood. Herein, the effects of pH, biomass, gold ion concentration, and photoinduction are evaluated to optimize gold nanoparticle (Au@NP) production by Shewanella. Results The highest amount of Au@NPs produced by SXM and MR-1 were 108 and 62 ppm, respectively, at pH 5 when 2.4 g/L biomass was immersed in 300 ppm gold ions and 50 mM lactate under a light intensity of 100 µmol/m2/s. By scanning election microscopy and zeta potential analysis, the proposed mechanism of Au@NP formation was that Shewanella used lactate as electron donors for the Mtr pathway, stimulated by photosensitive proteins resulting in the nucleation of NPs on the cell membrane. Besides, the resting cells retained the ability for biofabrication of nanoparticles for nearly 25 days. Conclusions The optimal conditions evaluated for Au@NPs production by Shewanella were biomass, pH, ions concentration, and photoinduction. To the best of our knowledge, this is the first attempt to explore a two-step mechanism for Au@NPs formation in Shewanella. First, the HAuCl4 solution reacted with sodium lactate to form metallic gold ions. Second, the metallic gold ions were adsorbed onto the outer membrane of cell, and the formation of Au@NPs at the surface was triggered. Shewanella-based Au@NPs production could be a potential ecofriendly solution for the recovery of Au ions from secondary resources like industrial waste

    Heat Transfer Enhancement by Detached S-Ribs for Twin-Pass Parallelogram Channel

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    Detached S-ribs are proposed to arrange in the stagger manner along two parallelogram straight channels interconnecting with a 180&deg; smooth-walled sharp bend for heat transfer enhancements. The detailed Nusselt number distributions over the two opposite channel endwalls at Reynolds numbers of 5000, 7500, 10,000, 12,500, 15,000 and 20,000 are measured using the steady-state infrared thermography method. The accompanying Fanning friction factors are evaluated from the measured pressure drops across the entire test channel. Having acquired the averaged heat transfer properties and Fanning friction factors, the thermal performance factors are determined under the criterion of constant pumping power consumptions. With the regional accelerated flows between the detached S-ribs and the channel endwall, the considerable heat transfer elevations from the Dittus&ndash;Boelter correlation levels are achieved. The comparative thermal performances between the two similar twin-pass parallelogram channels with detached 90&deg; and S-ribs disclose the higher regional heat transfer rates over the turning region and the larger Fanning frictions factors, leading to the lower thermal performance factors, for present test channel with the detached S-ribs. To assist design applications, two sets of empirical correlations evaluating the regionally averaged Nusselt numbers and Fanning friction factors are devised for present twin-pass parallelogram channel with the detached S-ribs

    The Investigation of Shallow Structures at the Meishan Fault Zone with Ambient Noise Tomography Using a Dense Array Data

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    Seismic monitoring relies on seismography. However, the high cost of seismic equipment has presented a challenge to increasing the density of seismic networks in previous decades. Due to the large station spacing and inferior coverage of stations, this situation has led to a loss of detail in many research results. Along with the improvement of technology, the problem of increasing the density of seismographic observations is no longer an impossible issue. This makes it feasible to deploy a dense seismic network for monitoring earthquakes. This study deployed a linear dense array across the Meishan Fault in west-southern Taiwan for the purpose of analyzing the shallow fault zone structure. While the 1906 Meishan earthquake occurred in a period when historic records were available, the surficial geology surveys of the Meishan Fault are challenging because farming and construction engineering have obscured the outcrop. Early surveys of the Meishan Fault were mainly seismic surveys. In recent decades, over thirty profiles have been completed. However, the reflection seismic records had poor signal-to-noise ratios because the Meishan Fault is buried under thick sediments. Thus, the shallow structure of the Meishan Fault is still not known in detail. This study applied double-beamforming tomography to a dense seismic array to obtain high-resolution images of the Meishan Fault zone. The result shows that there is a south-dipping interface near the fault trace as indicated by the Central Geological Survey of Taiwan. In addition, we observed velocity transitions of perturbation profiles that may be caused by a branch fault, the Chentsoliao Fault. This study demonstrates that the ambient noise double beamforming method is an effective tool for imaging the detailed shallow structure along with the dense seismic array

    Mechanical stretch via transforming growth factor-β1 activates microRNA-208a to regulate hypertrophy in cultured rat cardiac myocytes

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    MicroRNA-208a (miR208a) and mechanical stress play a key role in cardiac hypertrophy. The relationship between miR208a and mechanical stress in cultured cardiomyocytes has not been investigated. The molecular mechanisms underlying miR208a-induced hypertrophy of cardiomyocytes by mechanical stress is poorly understood. This study investigated whether miR208a is a critical regulator in cardiomyocyte hypertrophy under mechanical stretch. Methods: Neonatal rat cardiomyocytes grown on a flexible membrane base were stretched at 60 cycles/minute. MiR real-time quantitative assays were used to quantify miRs. A quantitative sandwich enzyme immunoassay technique was used to measure transforming growth factor-β1 (TGF-β1). A 3H-proline incorporation assay was used to measure protein synthesis. Results: Mechanical stretch significantly enhanced miR208a expression. Stretch significantly induced cardiomyocyte hypertrophic protein expression such as β-myosin heavy chain (MHCβ), thyroid hormone receptor-associated protein 100, myostatin, connexin 40, GATA4, and brain natriuretic peptide. MHCα was not induced by stretch. Overexpression of miR208a significantly increased MHCβ protein expression while pretreatment with antagomir208a significantly attenuated MHCβ protein expression induced by stretch and overexpression of miR208a. Mechanical stretch significantly increased the secretion of TGF-β1 from cultured cardiomyocytes. Exogenous addition of TGF-β1 recombinant protein significantly increased miR208a expression and pretreatment with TGF-β1 antibody attenuated miR208a expression induced by stretch. Mechanical stretch and overexpression of miR208a increased protein synthesis while antagomir208a attenuated protein synthesis induced by stretch and overexpression of miR208a. Conclusion: Cyclic stretch enhances miR208a expression in cultured rat cardiomyocytes. MiR208a plays a role in stretch-induced cardiac hypertrophy. The stretch-induced miR208a is mediated by TGF-β1

    Data analyses of honokiol-induced autophagy of human glioma cells in vitro and in vivo

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    This article contains raw and processed data related to a research, “Honokiol induces autophagic cell death in malignant glioma through reactive oxygen species-mediated regulation of the p53/PI3K/Akt/mTOR signaling pathway” (C.J. Lin, T.L. Chen, Y.Y. Tseng, G.J. Wu, M.H. Hsieh, Y.W. Lin, R.M. Chen, 2016) [1]. Data were obtained by immunoblotting analyses of light chain 3 (LC3)-II, beclin-1, Akt, and mTOR in human glioma U87 MG cells and mouse glioma tissues treated with honokiol, an active constituent extracted from the bark of Magnolia officinalis, “Honokiol induces autophagy of neuroblastoma cells through activating the PI3K/Akt/mTOR and endoplasmic reticular stress/ERK1/2 signaling pathways and suppressing cell migration” (P.S. Yeh, W. Wang, Y.A. Chang, C.J. Lin, J.J. Wang, R.M. Chen, 2016) [2]. The processed data show the effects of honokiol on induction of autophagy in human glioma U87 MG cells by analyzing levels of LC3-II, p62, and bectin-1, “Honokiol-induced apoptosis and autophagy in glioblastoma multiforme cells” (K.H. Chang, M.D Yan, C.J. Yao, P.C. Lin, G.M. Lai, 2013) [3]. In addition, chloroquine, a lysosomal inhibitor, was administered to the cells to further confirm honokiol-induced cell autophagy. Sequentially, mice with gliomas were created and treated with honokiol. Amounts of phosphorylated and non-phosphorylated Akt and mTOR in glioma tissues were analyzed to determine the possible mechanisms of honokiol-induced autophagy

    The effect of cerebral monitoring on recovery after sevoflurane anesthesia in ambulatory setting in children: A comparison among bispectral index, A-line autoregressive index, and standard practice

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    Background: The bispectral index (BIS) and A-line autoregressive index (AAI) are electroencephalogram-derived monitoring indices of anesthesia. This study evaluated the efficacy of BIS- and AAI-guided sevoflurane anesthesia in children receiving ambulatory urologic surgeries. Methods: One hundred sixty children (aged 3–12 years) undergoing ambulatory urologic surgery were randomized to receive sevoflurane anesthesia controlled either solely by clinical parameters (standard practice group), BIS-guided group within the BIS range of 40–60 (BIS group), or AAI-guided group within the AAI range of 15–30 (AAI group). The primary outcome was the recovery time, and the secondary outcome was the quality of recovery, including the incidence of emergency delirium measured by Pediatric Anesthesia Emergence Delirium score, incidence of postoperative nausea and vomiting, and parental satisfaction. Results: Compared with the standard practice group, patients with BIS or AAI monitoring had shortened recovery time and consumed less sevoflurane. There were no significant differences in the incidences of emergence delirium, postoperative nausea and vomiting, or parental satisfaction among the three groups. Conclusion: BIS- and AAI- guided titration sevoflurane anesthesia could result in shortened recovery and reduced sevoflurane concentration and consumption without affecting the quality of recovery in children receiving ambulatory urologic surgery. The beneficial effects of AAI- and BIS-guided anesthesia in pediatric ambulatory surgeries are similar
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