Search Results
Results 201 - 250 of 1589
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Islam Mohammad Mahbub - - 2009
Thioglucoside glucohydrolase (myrosinase), TGG1, is a strikingly abundant protein in Arabidopsis guard cells. We investigated responses of tgg1-3, tgg2-1 and tgg1-3 tgg2-1 mutants to abscisic acid (ABA) and methyl jasmonate (MeJA) to clarify whether two myrosinases, TGG1 and TGG2, function during stomatal closure. ABA, MeJA and H(2)O(2) induced stomatal closure ...
Beckers Simone - - 2010
A dynamic respiration assay based on luminescence decay time detection of oxygen for high throughput toxicological assessment is presented. The method uses 24-well plates (OxoDishes) read with the help of a sensor dish reader placed in a humidified CO(2)-incubator. Adherent primary rat hepatocytes and the human hepatic cell line Hep ...
Lu Zhisong - - 2009
Quantum dots-induced cell growth inhibition effect and its photophysical mechanism were investigated in this report. Cell growth curve and atomic force microscopy show that QDs block cell division to inhibit the growth of bacterial cells. On the basis of combined biological and physical discoveries from cytochrome c reduction assay, hydrodynamic ...
van der Toorn Marco - - 2009
Reactive oxygen species (ROS) present in cigarette smoke (CS) are thought to contribute to the development of COPD. Although CS-ROS can hardly enter airway epithelial cells, and certainly not the circulation, systemic levels of ROS have been found to be elevated in COPD patients. We hypothesize that lipophilic components present ...
Sakdee Jaruma Beau - - 2009
INTRODUCTION: Postnatal human dental pulp is a potentially promising source of progenitor cells. Sustaining and amplifying progenitor cell populations would be beneficial for basic science research with application in pulpal regeneration. Hypoxia has been observed to promote the undifferentiated cell state in various stem cell populations. The purpose of this ...
Petit Emile - - 2009
Reactive oxygen species (ROS) have been suggested to participate in tumor emergence due to their mitogenic and apoptotic signaling, and as contributors to DNA structural damage. Here we report that progesterone and various synthetic steroids with progestin potencies (norethisterone acetate, MPA, and Tibolone) counteract cell growth induced by hydrogen peroxide ...
Kim Hyung-Ryong - - 2009
This study investigated the molecular mechanism by which Bax inhibitor 1 (BI1) abrogates the accumulation of reactive oxygen species (ROS) in the endoplasmic reticulum (ER). Electron uncoupling between NADPH-dependent cytochrome P450 reductase (NPR) and cytochrome P450 2E1 (P450 2E1) is a major source of ROS on the ER membrane. ER ...
Deng Xiaobing - - 2009
The kinase Mirk/dyrk1B mediated the clonogenic growth of pancreatic cancer cells in earlier studies. It is now shown that Mirk levels increased 7-fold in SU86.86 pancreatic cancer cells when over a third of the cells were accumulated in a quiescent G(0) state, defined by Hoechst/Pyronin Y staining. Depletion of Mirk ...
Groeger Gillian - - 2009
Reactive oxygen species (ROS) have traditionally been viewed as a toxic group of molecules; however, recent publications have shown that these molecules, including H(2)O(2), can also strongly promote cell survival. Even though the retina has a large capacity to produce ROS, little is known about its non-mitochondrial sources of these ...
Zhao Baozhong - - 2009
The water-soluble fullerene derivative gamma-cyclodextrin bicapped C(60) [(gamma-CyD)(2)/C(60), CDF0] has several clinical applications, including use as a drug carrier to bypass the blood ocular barriers or a photosensitizer to treat tumors in photodynamic therapy. We have assessed the potential ocular toxicity of (gamma-CyD)(2)/C(60) and its aggregated derivatives induced by UVA ...
Chung Woon-Gye - - 2009
Proanthocyanidins (PCs) have been shown to suppress the growth of diverse human cancer cells and are considered as promising additions to the arsenal of chemopreventive phytochemicals. An oligomeric mixture of PCs from hops (Humulus lupulus) significantly decreased cell viability of human colon cancer HT-29 cells in a dose-dependent manner. Hop ...
Shao Junfei - - 2009
Resveratrol (Res) has been reported to elicit many cellular responses including cell cycle arrest, differentiation, and apoptosis. This makes it a novel and potential anticancer agent. Moreover, the lipophilicity of Res raises the possibility of its application as a potential model drug in nanoparticle based delivery systems. Resveratrol is incorporated ...
Wilhelm Jirí - - 2009
Reactive oxygen species (ROS) play several biological roles. We investigated the applicability of fluorescent probes for their detection (i) in rabbit lens epithelial cells during ageing in culture, and (ii) in thin sections of rat heart. We used dihydroethidium (DHE), dichlorofluorescin (DCFH), and dihydrorhodamine 123 (DHR) together with detection of ...
Acosta Miguel A - - 2009
We present the development and characterization of fluorescent oxygen-sensing microparticles designed for measuring oxygen concentration in microenvironments existing within standard cell culture and transparent three-dimensional (3D) cell scaffolds. The microparticle synthesis employs poly(dimethylsiloxane) to encapsulate silica gel particles bound with an oxygen-sensitive luminophore as well as a reference or normalization ...
Borgmann Sabine - - 2009
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play a crucial role in chemical signaling processes of biological cells. Electrochemistry is one of the rare methods able to directly detect these species. ROS and RNS can be monitored in the local microenvironment of cells in real time at the ...
Chan Elsa C - - 2009
The superoxide generating enzyme NADPH oxidase has received much attention as a major cause of oxidative stress underlying vascular disease. However, there is increasing evidence that oxidant signaling involving NADPH oxidase has other important roles in cell biology. Nox family proteins are the catalytic, electron-transporting subunits of the NADPH oxidase ...
Steinbrenner Holger - - 2009
Reactive oxygen species (ROS) are derived from cellular oxygen metabolism and from exogenous sources. An excess of ROS results in oxidative stress and may eventually cause cell death. ROS levels within cells and in extracellular body fluids are controlled by concerted action of enzymatic and non-enzymatic antioxidants. The essential trace ...
Verbelen P J - - 2009
The volumetric productivity of the beer fermentation process can be increased by using a higher pitching rate (i.e., higher inoculum size). However, the decreased yeast net growth observed in these high cell density fermentations can have a negative impact on the physiological stability throughout subsequent yeast generations. The use of ...
Sud Dhruv - - 2009
Calibration of fluorescent optical sensors for accurate, quantitative intracellular measurements in vivo suffers from lack of a representative medium that appropriately simulates the molecular complexity of the cytosol. We present a novel protocol for accurate intracellular oxygen sensing via fluorescence lifetime imaging microscopy (FLIM) using cell lysate-FLIM measurements to correct ...
Popa Radu - - 2009
Individual magnetosome-containing magnetic mineral particles (MMP) from magnetotactic bacteria grow rapidly such that only a small fraction (5%) of all magnetosomes contain dwarf (< or =20 nm) MMP. Studies of the developmental stages in the growth of MMP are difficult due to the absence of techniques to separate dwarf from ...
Wang XiaoBing - - 2009
This study is to test the sensitivities of different tumor cells to ultrasound irradiation at the frequency of 2.2 MHz for 60 s duration, and investigate the potential mechanism underlying different sensitivities. Three murine tumor models with distinct aggressiveness (S180, H-22 and EAC) were exposed to ultrasound to evaluate their ...
So Cheung-Wai - - 2010
Photodynamic therapy is a treatment that combines the use of three non-toxic components, viz. photosensitiser, light and oxygen to cause localised oxidative photodamage. In the present study, the antifungal effect of the photosensitiser, BAM-SiPc, an unsymmetrical bisamino phthalocyanine, was investigated. BAM-SiPc was effective in photo-inactivating Candida albicans in a dose-dependent ...
Robinson John M - - 2009
Phagocytic leukocytes, when appropriately stimulated, display a respiratory burst in which they consume oxygen and produce superoxide anions. Superoxide is produced by the phagocyte NADPH-oxidase system which is a multiprotein complex that is dissociated in quiescent cells and is assembled into the functional oxidase following stimulation of these cells. Also ...
Bedogni Barbara - - 2009
The tissue microenvironment plays a critical role in cell survival and growth and can contribute to cell transformation and tumor development. Cellular interactions with the stroma and with other cells provide key signals that control cellular arrest or division, survival or death, and entrance or exit from a quiescent state. ...
Umekawa Tohru - - 2009
OBJECTIVE To test the hypothesis that exposure of a renal epithelial cell line, NRK52E, to calcium oxalate monohydrate crystals (COM) would up-regulate NADPH oxidase subunit p47(phox), enhance superoxide production and increase monocyte chemoattractant protein-1 (MCP-1) and osteopontin mRNA levels. MATERIALS AND METHODS Confluent cultures of NRK52E cells were exposed to ...
Zhang Rui - - 2009
Macula densa cells produce superoxide (O2-) during tubuloglomerular feedback primarily via NAD(P)H oxidase (NOX). The purpose of the present study was to determine NOXs expressed by the macula densa and the role of each one in NaCl-induced O2- production. To identify which isoforms are expressed, we applied single-cell RT-PCR to ...
Yoshii Hanako - - 2009
Oxygen is essential for life, and cells have therefore developed numerous adaptive responses to oxygen change. Here, we examined the difference in oxygen-control functions of human (HE), mouse (ME), and Syrian hamster embryo (SHE) cells cultured under different oxygen conditions (0.5%, 2% and 20%), and also examined whether oxygen tensions ...
Chou Duen-Suey - - 2009
In a previous study, we demonstrated that baicalein induces hydroxyl radical formation in human platelets but the mechanisms are unclear. Herein, we show, using an electron spin resonance technique, that baicalein also induces hydroxyl radical formation in B16F10 melanoma cells in a dose-dependent manner. Baicalein produced superoxide anions in the ...
Guo Shuhong - - 2009
Hypoxia inducible factor 1 (HIF-1) has been suggested to play a critical role in the fate of cells exposed to hypoxic stress. However, the mechanism of HIF-1-regulated cell survival is still not fully understood in ischemic conditions. Redox status is critical for decisions of cell survival, death and differentiation. We ...
Seo Kyo Seong - - 2009
The biochemical oxygen demand (BOD) determination was studied using a novel flow injection analysis (FIA) system with encapsulated Saccharomyces cerevisiae cells and an oxygen electrode and was compared with conventional 5-day BOD tests. S. cerevisiae cells were packed in a calcium alginate capsule at a dry cell weight of 250 ...
Deshpande Rahul Ravi - - 2009
We show the application of a novel optical on-line sensor fixed in spinner flasks for the online monitoring of dissolved O(2) concentrations during mammalian cell growth. Using this sensor that requires only minute changes to the flask to be made, we could determine the volumetric O(2) transfer coefficient as well ...
Chung Woon-Gye - - 2009
Proanthocyanidins (PCs) have been shown to suppress the growth of diverse human cancer cells and are considered as promising additions to the arsenal of chemopreventive phytochemicals. An oligomeric mixture of PCs from hops (Humulus lupulus) significantly decreased cell viability of human colon cancer HT-29 cells in a dose-dependent manner. Hop ...
Molter Timothy W - - 2009
Due to interest in cell population heterogeneity, the development of new technology and methodologies for studying single cells has dramatically increased in recent years. The ideal single cell measurement system would be high throughput for statistical relevance, would measure the most important cellular parameters, and minimize disruption of normal cell ...
Kuimova Marina K - - 2009
Singlet molecular oxygen, O(2)(a(1)Delta(g)), can be created in a single cell from ground-state oxygen, O(2)(X(3)Sigma(g)(-)), upon focused laser irradiation of an intracellular sensitizer. This cytotoxic species can subsequently be detected by its 1270 nm phosphorescence (a(1)Delta(g) --> X(3)Sigma(g)(-)) with subcellular spatial resolution. The singlet oxygen lifetime determines its diffusion distance ...
Wang Ling - - 2009
This study investigated the factors influencing the oxygen metabolism of aortic valve interstitial cells (VICs). Porcine VICs in cell suspension at different passages, and adhered to coverslips at different confluencies, as well as fresh porcine valve leaflets, were incubated in an oxygen respiration chamber at 37 degrees C in Dulbecco's ...
S.L. Ho
The design, fabrication and performance evaluation of a passive direct methanol fuel cell (DMFC) operated at ambient condition with an active area of 7.5 cm&lt;SUP&gt;2 &lt;/SUP&gt;is studied in this research. The fuel cell is air-breathing and passive without any external pumps or auxiliary devices. Oxygen is taken from the surrounding ...
Verklan M Terese - - 2009
Hypoxic-ischemic encephalopathy (HIE) is one of the most important complications found in the newborn period. It is the result of a deprivation of oxygen and glucose to the neural tissue, which may be the result of either hypoxemia or ischemia. Experimental animal research and clinical observations in humans have noted ...
Matsui Satoshi - - 2009
The present study was conducted to investigate the effects of reactive oxygen species (ROS) on the calcification ability of human dental pulp (HDP) cells. HDP cells were treated with 100 mumol/L hydrogen peroxide (H(2)O(2)) for 5 or 10 minutes (5-min ROS group and 10-min ROS group) to investigate the mechanism ...
Maraldi Tullia - - 2009
The mechanism involved in the prosurvival effect of interleukin-3 on the human acute myeloid leukaemia cell line M07e is investigated. A decrease in intracellular reactive oxygen species (ROS) content, glucose transport activity and cell survival was observed in the presence of inhibitors of plasma membrane ROS sources, such as diphenylene ...
Nogawa Hisashi - - 2009
BACKGROUND AND OBJECTIVE: Reactive oxygen species (ROS) play an important role in the pathogenesis of various respiratory diseases. Carbocisteine, a mucoregulatory drug, is used in the treatment of several disease states but little information is available about its scavenger effects on ROS. The present study was designed to examine the ...
Engler Ivan - - 2009
In the nature including the human organism there are 5 reactive oxygen species (ROS): O2, O2-*, O2+*, 1O2, O3 with different electromagnetic characteristics and biological effects. The effects of enrichment of medical oxygen O2 with traces of ROS on various cells were tested in experiments. METHODS: Human embryonic lung fibroblasts ...
Dayan Frédéric - - 2009
Accumulation of HIF-1alpha during normoxic conditions at high cell density has previously been shown to occur and can be used to stabilize HIF-1alpha protein in the absence of a specific anaerobic chamber. However, the impact and origin of this pool of HIF-1alpha, obtained under normoxia, has been underestimated. In this ...
Shaikh Shamim B - - 2009
Exposure to toxins/chemicals is considered to be a significant risk factor in the pathogenesis of Parkinson's disease (PD); one putative chemical is the naturally occurring herbicide rotenone that is now used widely in establishing PD models. We, and others, have shown that chronic low dose rotenone treatment induces excessive accumulation ...
Raclavský V - - 2009
Cryptococcus neoformans was grown in 96-well microtiter plates sealed by foil which is less than 0.01 % permeable to oxygen. On day 14 of the cultivation, we observed peculiar clusters of small droplike daughter cells arranged around < or = 4 % of mother cells. The fact that most of ...
Dat Nguyen Tien - - 2009
Hypoxia-inducible factor-1 (HIF-1) is the central mediator of cellular responses to low oxygen concentrations and vital to many aspects of cancer biology. Bioassay-guided fractionation of the chloroform-soluble extracts of Morus species using a hypoxia response element (HRE)-dependent reporter assay led to identification of six benzofurans (1-6) and two chalcone-derived Diels-Alder ...
Warnke Christian - - 2009
The metabolic dynamics of yeast cells is controlled by electric pulses delivered through a spatially extended yeast cell/Au electrode interface. Concomitant with voltage pulses, oxygen is generated electrolytically at the electrode surface and delivered to the cells. The generation of oxygen was investigated in dependence of the applied voltage, width ...
Jiang Fan - - 2009
NADPH oxidase-derived reactive oxygen species are implicated in apoptosis in certain kidney cells. On the other hand, NADPH oxidase is also involved in promoting cell proliferation in the kidney. The two faces of NADPH oxidase in these situations prompt us to argue that the role of this enzyme in various ...
Cossarizza Andrea - - 2009
Reactive oxygen species (ROS) are continuously produced in the cell as a consequence of aerobic metabolism, and are controlled by several antioxidant mechanisms. An accurate measurement of ROS is essential to evaluate the redox status of the cell, or the effects of molecules with the pro-oxidant or antioxidant activity. Here ...
Lluis Josep M - - 2009
Hypoxia-mediated HIF-1alpha stabilization and NF-kappaB activation play a key role in carcinogenesis by fostering cancer cell survival, angiogenesis and tumor invasion. Gangliosides are integral components of biological membranes with an increasingly recognized role as signaling intermediates. In particular, ganglioside GD3 has been characterized as a proapoptotic lipid effector by promoting ...
Desai Nisarg R - - 2009
Hazardous health effects stemming from exposure to radiofrequency electromagnetic waves (RF-EMW) emitted from cell phones have been reported in the literature. However, the cellular target of RF-EMW is still controversial. This review identifies the plasma membrane as a target of RF-EMW. In addition, the effects of RF-EMW on plasma membrane ...
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