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Registros recuperados: 992 | |
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Berrocal,Liliana; Fuentes,Juan A; Nicole Trombert,A; Jofré,Matías R; Villagra,Nicolás A; Valenzuela,Luis M; Mora,Guido C. |
BACKGROUND: Salmonella enterica serovar Typhi (S. Typhi) stg operon, encoding a chaperone/usher fimbria (CU), contributes to an increased adherence to human epithelial cells. However, one report suggests that the presence of the Stg fimbria impairs the monocyte-bacteria association, as deduced by the lower level of invasion to macrophage-like cells observed when the stg fimbrial cluster was overexpressed. Nevertheless, since other CU fimbrial structures increase the entry of S. Typhi into macrophages, and considering that transcriptomic analyses revealed that stg operon is indeed expressed in macrophages, we reassessed the role of the stg operon in the interaction between S. Typhi strain STH2370 and human cells, including macrophage-like cells and... |
Tipo: Journal article |
Palavras-chave: Salmonella Typhi; Stg; Fimbriae; Adherence; Association bacteria-eukaryotic cells. |
Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100034 |
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Manojlovic,Nedeljko T; Vasiljevic,Perica J; Gritsanapan,Wandee; Supabphol,Roongtawan; Manojlovic,Ivana. |
The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identifed by relative retention time and spectral data. This is the frst time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic signifcance because very little has been published on the secondary metabolites present in Laurera species.... |
Tipo: Journal article |
Palavras-chave: Anthraquinones; Antioxidant activity; Laurera benguelensis; Xanthones. |
Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602010000200004 |
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SEZER,METIN; TEKELIOGLU,OGUZ. |
The Japanese quail lays eggs with colourful and patterned shells which make the eggshell colour difficult to classify. In this study, the method of measuring colour of patchy eggs using image analyses and its power to discriminate among individual variation were established. Estimated repeatability for egg colour and proportion of patterned areas was high (>0.58), suggesting intermedíate or high heritability of eggshell colour characteristics. Three components have been identified as significant in discriminant function analysis. These three components explained 91.4% of the total variance in egg colour characteristics. In cluster analysis, 78.3% of the eggs that were collected from 15 females were correctly classified. This study indicates that... |
Tipo: Journal article |
Palavras-chave: Eggshell colour; Image analysis; Individual variation; Repeatability. |
Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602009000100010 |
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Arai,Takaomi; Amalina,Razikin; Bachok,Zainudin. |
BACKGROUND: In order to understand feeding ecology and habitat use of coral reef fish, fatty acid composition was examined in five coral reef fishes, Thalassoma lunare, Lutjanus lutjanus, Abudefduf bengalensis, Scarus rivulatus and Scolopsis affinis collected in the Bidong Island of Malaysian South China Sea. RESULTS: Proportions of saturated fatty acids (SAFA) ranged 57.2% 74.2%, with the highest proportions in fatty acids, the second highest was monounsaturated fatty acids (MUFA) ranged from 21.4% to 39.0% and the proportion of polyunsaturated fatty acids (PUFA) was the lowest ranged from 2.8% to 14.1%. Each fatty acid composition differed among fishes, suggesting diverse feeding ecology, habitat use and migration during the fishes' life history in the... |
Tipo: Journal article |
Palavras-chave: Coral fish; Habitat ecology; Migration; South China Sea; Biochemical signature; Malaysia. |
Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100013 |
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ORTEGA,XIMENA; POLANCO,RUBÉN; CASTAÑEDA,PATRICIA; PEREZ,LUZ M. |
The development of an effective hypersensitive response (HR) in any plant system relies, not only in their gene composition and expression, but also on an effective and rapid signal transduction system. Lemon seedlings induce the phenylpropanoid pathway, which results in the de novo biosynthesis of the phytoalexin scoparone, as part of the hypersensitive response against Alternaria alternata. In order to elucidate some of the signaling elements that participate in the development of HR in lemon seedlings, we used several compounds that are known as activators or inhibitors of signal transduction elements in plants or in animal cells. Lemon seedlings treated either with cholera toxin or with phorbol 12-myristate 13-acetate (PMA), in the absence of A.... |
Tipo: Journal article |
Palavras-chave: Citrus limon; Hypersensitive response; Signal transduction. |
Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000300012 |
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Rosas,Carlos; Sinning,Mariana; Ferreira,Arturo; Fuenzalida,Marcela; Lemus,David. |
BACKGROUND: During the last few years it has been shown in several laboratories that Celecoxib (Cx), a non-steroidal anti-inflammatory agent (NSAID) normally used for pain and arthritis, mediates antitumor and antiangiogenic effects. However, the effects of this drug on a tumor cell line resistant to chemotherapeutical drugs used in cancer have not been described. Herein we evaluate the angiogenic and antitumor effects of Cx in the development of a drug-resistant mammary adenocarcinoma tumor (TA3-MTXR). RESULTS: Cx reduces angiogenesis in the chick embryonic chorioallantoic membrane assay (CAM), inhibits the growth and microvascular density of the murine TA3-MTXR tumor, reduces microvascular density of tumor metastases, promotes apoptosis and reduces... |
Tipo: Journal article |
Palavras-chave: Angiogenesis; Celecoxib; Tumor. |
Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602014000100027 |
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Zhang,Li; Tan,Jinyun; Jiang,Xiaoping; Qian,Weiwei; Yang,Ting; Sun,Xijun; Chen,Zhaohui; Zhu,Qiwen. |
Abstract Background CCL2 was up-regulated in neurons and involved in microglia activation and neurological decline in mice suffering from hepatic encephalopathy (HE). However, no data exist concerning the effect of neuron-derived CCL2 on microglia activation in vitro. Methods The rats were pretreated with CCL2 receptor inhibitors (INCB or C021, 1 mg/kg/day i.p.) for 3 days prior to thioacetamide (TAA) administration (300 mg/kg/day i.p.) for inducing HE model. At 8 h following the last injection (and every 4 h after), the grade of encephalopathy was assessed. Blood and whole brains were collected at coma for measuring CCL2 and Iba1 expression. In vitro, primary neurons were stimulated with TNF-α, and then the medium were collected for addition... |
Tipo: Journal article |
Palavras-chave: Hepatic encephalopathy; Neuron; Microglia; Chemokine CC motif ligand 2. |
Ano: 2017 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602017000100218 |
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HIDALGO,CECILIA; BULL,RICARDO; MARENGO,JUAN J; PÉREZ,CLAUDIO F; DONOSO,PAULINA. |
The effects of redox reagents on the activity of the intracellular calcium release channels (ryanodine receptors) of skeletal and cardiac muscle, or brain cortex neurons, was examined. In lipid bilayer experiments, oxidizing agents (2,2'-dithiodipyridine or thimerosal) modified the calcium dependence of all single channels studied. After controlled oxidation channels became active at sub µM calcium concentrations and were not inhibited by increasing the calcium concentration to 0.5 mM. Subsequent reduction reversed these effects. Channels purified from amphibian skeletal muscle exhibited the same behavior, indicating that the SH groups responsible for modifying the calcium dependence belong to the channel protein. Parallel experiments that... |
Tipo: Journal article |
Palavras-chave: Calcium dependence; Neurons; Redox state; Ryanodine receptors; Sarcoplasmic reticulum; Skeletal and cardiac muscle. |
Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000200011 |
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GHATPANDE,SATISH; SHAFIQ,SAIYID; SIDDIQUI,M.A.Q.. |
Recent gene knock-out studies in mice have suggested that ventricular myosin light chain-2 (vMLC2) has a role in the regulation of cardiogenic development and that perturbation in expression of vMLC2 is linked to the onset of dilated cardiomyopathy. In an attempt to develop an avian model for such studies, we examined the expression pattern of vMLC2 in chicken embryos at various stages and analyzed the effect of antisense oligonucleotide-mediated interference of vMLC2 function in cultures of whole embryos. Our results showed vMLC2 to be a specific marker for ventricular chamber throughout chicken embryonic development and antisense vMLC2 treatment of primitive streak stage (stage 4) embryos to produce pronounced dilation of heart tube with severe... |
Tipo: Journal article |
Palavras-chave: Cardiogenesis; Cardiomyopathy; Myosin light chains; Tissue culture. |
Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602001000100009 |
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Zengin,Fikriye. |
The effects of nickel, cobalt, chromium and zinc on the content of vitamins A, E and C, malondialdehyde (MDA), chlorophyll and carotenoids were investigated in bean seedlings (Phaseolus vulgaris L.) grown in Hoagland solution Control and heavy metal-treated plants were grown for ten days in Hoagland solution. Vitamin A, E, and C content were measured in primary leaves by high performance liquid chromatographic (HPLC). MDA, chlorophyll and carotenoids were measured in leaves by spectrophotometer. In heavy metal treated plants, the levels of MDA, vitamins A, E and C and carotenoids significantly increased, while chlorophyll content decreased in leaves of seedlings. The results indicate that heavy metals caused an oxidative stress in bean plants. The... |
Tipo: Journal article |
Palavras-chave: Heavy metal; Vitamins A; E and C; MDA; Chlorophyll and carotenoids. |
Ano: 2013 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000100012 |
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BACIGALUPO,FÉLIX; HUERTA,DANIELA; MONTEFUSCO-SIEGMUND,RODRIGO. |
In this concise review we discuss some of the complex edges of the concept of death that arose after the notorious advances in science and medicine over the last 50 years, in which the classical cardio-pulmonary criteria have led to the neurological criteria of death. New complicated questions like the definition of death and the operational criteria for diagnosing it have arisen and we think that they are far from being adequately and satisfactorily solved. A number of important issues -like the reliability and differences between cardio-pulmonary versus brain based criteria of death, if death is an event or a process, the meaning of integration and irreversibility- have not yet received sufficient attention. Here we have approached the death problem from... |
Tipo: Journal article |
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Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602007000500014 |
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MACKENZIE,LAUREN; RODERICK,H. LLEWELYN; PROVEN,ANDREW; CONWAY,STUART J; BOOTMAN,MARTIN D. |
Inositol 1,4,5-trisphosphate (InsP3) is an established calcium-mobilizing messenger, which is well-known to activate Ca2+ signaling in many cell types. Contractile cardiomyocytes express hormone receptors that are coupled to the production of InsP3. Such cardioactive hormones, including endothelin, may have profound inotropic and arrhythmogenic actions, but it is unclear whether InsP3 underlies any of these effects. We have examined the expression and localization of InsP3 receptors (InsP3Rs), and the potential role of InsP3 in modulating cardiac excitation-contraction coupling (EC coupling). Stimulation of electrically-paced atrial and ventricular myocytes with a membrane-permeant InsP3 ester was found to evoke an increase in the amplitudes of action... |
Tipo: Journal article |
Palavras-chave: Calcium; Cardiac; Inositol; Arrhythmia; Ryanodine. |
Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000400008 |
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LEIVA-SALCEDO,ELIAS; PEREZ,VIVIANA; ACUÑA-CASTILLO,CLAUDIO; WALTER,ROBIN; SIERRA,FELIPE. |
Serum levels of T-kininogen increase dramatically as rats approach the end of their lifespan. Stable expression of the protein in Balb/c 3T3 fibroblasts leads to a dramatic inhibition of cell proliferation, as well as inhibition of the ERK signaling pathway. T-kininogen is a potent inhibitor of cysteine proteinases, and we have described that the inhibition of ERK activity occurs, at least in part, via stabilization of the MAP kinase phosphatase, MKP-1. Since fibroblasts are not a physiological target of T-kininogen, we have now purified the protein from rat serum, and used it to assess the effect of T-kininogen on endothelial cells. Adding purified T-kininogen to EAhy 926 hybridoma cells resulted in inhibition of basal ERK activity levels, as estimated... |
Tipo: Journal article |
Palavras-chave: Aging; Endothelial cells; ERK pathway; Kininogen; Kinins. |
Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000200020 |
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LIMA,ANDRÉA C PAULA; ARRIAGADA,CHRISTIAN; TORO,RODRIGO; CÁRDENAS,ANA MARÍA; CAVIEDES,RAÚL; FERREIRA,SERGIO T; CAVIEDES,PABLO. |
We have previously characterized a number of small molecule organic compounds that prevent the aggregation of the β-amyloid peptide and its neurotoxicity in hippocampal neuronal cultures. We have now evaluated the effects of such compounds on amyloid precursor protein (APP) accumulation in the CTb immortalized cell line derived from the cerebral cortex of a trisomy 16 mouse, an animal model of Down's syndrome. Compared to a non-trisomic cortical cell line (CNh), CTb cells overexpress APP and exhibit slightly elevated resting intracellular Ca2+ levéis ([Ca2+]¡). Here, we show that the compounds 2,4-dinitrophenol, 3-nitrophenol and 4-anisidine decreased intracellular accumulation of APP in CTb cells. Those compounds were non-toxic to the cells, and... |
Tipo: Journal article |
Palavras-chave: Alzheimer's disease; Down syndrome; Intracellular amyloid; Murine trisomy 16; Small molecule inhibitors. |
Ano: 2008 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602008000200001 |
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FELIPE BARROS,LUIS; CASTRO,JOEL; BITTNER,CARLA X.. |
Cell death is preceded by severe disruption of inorganic ion homeostasis. Seconds to minutes after an injury, calcium, protons, sodium, potassium and chloride are exchanged between the cell and its environment. Simultaneously, ions are shifted between membrane compartments inside the cell, whereby mitochondria and endoplasmic reticulum play a crucial role. Depending of the type and severity of injury, two mutually exclusive metastable states can be reached, which predict the final outcome. Cells characterized by large increases in cytosolic [Ca2+], [Na+]; and [Mg2+] swell and die by necrosis; alternatively, cells characterized by high [H+]and low [K+], with normal [Na+] and normal to moderate [Ca2+] increases die by apoptosis. The levels of these ions... |
Tipo: Journal article |
Palavras-chave: Cell death; Membrane channels; Apoptosis; Necrosis. |
Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000200012 |
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Registros recuperados: 992 | |
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