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| Registros recuperados: 992 | |
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| BENDER,FLORENT; MONTOYA,MARGARITA; MONARDES,VIRGINIA; LEYTON,LISETTE; QUEST,ANDREW F.G.. |
| Caveolae are small, flask-shaped invaginations of the plasma membrane present on a large number of mammalian cells. Recent results obtained with knock-out mice for the gene caveolin-1 demonstrate that expression of caveolin-1 protein is essential for caveolae formation in vivo. Caveolae are implicated in a wide variety of cellular events including transcytosis, cholesterol trafficking and as cellular centers important in coordinating signalling events. Caveolae share this role and the property of detergent insolubility with plasma membrane assemblies rich in glycosphingolipids and cholesterol, often called lipid rafts, but preferably referred to here as caveolae-like membrane domains. Due to such widespread presence and usage in cellular function, caveolae... |
| Tipo: Journal article |
Palavras-chave: Caveolae; Caveolae-like domains; Lipid rafts; Caveolin-1; Tumor suppressor; Colon carcinoma cells; Microarray analysis. |
| Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602002000200006 |
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| GAO,HUAN; CAI,SHENGLI; YAN,BINLUN; CHEN,BAIYAO; YU,FEI. |
| To address whether there are differences of variation among repeat motif types and among taxonomic groups, we present here an analysis of variation and correlation of dinucleotide microsatellite repeats in eukaryotic genomes. Ten taxonomic groups were compared, those being primates, mammalia (excluding primates and rodentia), rodentia, birds, fish, amphibians and reptiles, insects, molluscs, plants and fungi, respectively. The data used in the analysis is from the literature published in the Journal of Molecular Ecology Notes. Analysis of variation reveals that there are no significant differences between AC and AG repeat motif types. Moreover, the number of alleles correlates positively with the copy number in both AG and AC repeats. Similar conclusions... |
| Tipo: Journal article |
Palavras-chave: Microsatellites; Eukaryotic genomes; Variation of SSR; Copy number; Meta-analysis. |
| Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602009000300011 |
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| Marthandan,Shiva; Menzel,Uwe; Priebe,Steffen; Groth,Marco; Guthke,Reinhard; Platzer,Matthias; Hemmerich,Peter; Kaether,Christoph; Diekmann,Stephan. |
| BACKGROUND: Cellular senescence is induced either internally, for example by replication exhaustion and cell division, or externally, for example by irradiation. In both cases, cellular damages accumulate which, if not successfully repaired, can result in senescence induction. Recently, we determined the transcriptional changes combined with the transition into replicative senescence in primary human fibroblast strains. Here, by γ-irradiation we induced premature cellular senescence in the fibroblast cell strains (HFF and MRC-5) and determined the corresponding transcriptional changes by high-throughput RNA sequencing. RESULTS: Comparing the transcriptomes, we found a high degree of similarity in differential gene expression in replicative as well... |
| Tipo: Journal article |
Palavras-chave: Senescence Fibroblasts γ -irradiation Aging Transcriptome analysis DNA repair. |
| Ano: 2016 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602016000100034 |
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| BOTA ARQUÉ,ALEXANDRE. |
| La revolución biotecnológica afronta grandes retos, entre ellos la participación social, la bioseguridad y la protección tanto del germoplasma como del conocimiento ancestral que de él se derivan. Para afrontar estos dilemas se plantea la necesidad de buscar una corresponsabilización de todos los actores del desarrollo biotecnológico. En este artículo se realiza un correlato partiendo de la reflexión ya iniciada por la comunidad médica con sus pautas éticas internacionales para la investigación biomédica en seres humanos, CIOMS, versus la biotecnología para buscar una corresponsabilización de los tecnocientíficos, biotecnólogos en sus investigaciones con la pretensión utópica de buscar un desarrollo biotecnológico mas respetuoso con el hombre y con su... |
| Tipo: Journal article |
Palavras-chave: Bioética; Biotecnología; Empoderamiento. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602003000200005 |
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| ITURRIAGA,RODRIGO. |
| Nitric oxide (NO) has been proposed as an inhibitory modulator of carotid body chemosensory responses to hypoxia. It is believed that NO modulates carotid chemoreception by several mechanisms, which include the control of carotid body vascular tone and oxygen delivery and reduction of the excitability of chemoreceptor cells and petrosal sensory neurons. In addition to the well-known inhibitory effect, we found that NO has a dual (dose-dependent) effect on carotid chemoreception depending on the oxygen pressure level. During hypoxia, NO is primarily an inhibitory modulator of carotid chemoreception, while in normoxia NO increased the chemosensory activity. This excitatory effect produced by NO is likely mediated by an impairment of mitochondrial electron... |
| Tipo: Journal article |
Palavras-chave: Carotid body; Chemoreceptor; Cytochrome oxidase; Hypoxia; Nitric oxide; Oxidative phosphorylation. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602001000200019 |
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| Cerda,Oscar A; Núñez-Villena,Felipe; Soto,Sarita E; Ugalde,José Manuel; López-Solís,Remigio; Toledo,Héctor. |
| About half of the human population is infected with Helicobacter pylori, a bacterium causing gastritis, peptic ulcer and progression to gastric cancer. Chemotaxis and flagellar motility are required for colonization and persistence of H. pylori in the gastric mucus layer. It is not completely clear which chemical gradients are used by H. pylori to maintain its position. TlpA, a chemotaxis receptor for arginine/ bicarbonate, has been identified. This study aimed to find out whether tlpA gene expression is required for the chemotactic response to arginine/bicarbonate. Wild-type motile H. pylori ATCC 700392 and H. pylori ATCC 43504, a strain having an interrupted tlpA gene, were used. Also, a tlpA-knockout mutant of H. pylori 700392 (H. pylori 700-tlpA::cat)... |
| Tipo: Journal article |
Palavras-chave: TlpA; Chemotaxis; Helicobacter pylori; Arginine; Bicarbonate. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602011000300009 |
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| BERNAL,FABIÁN; HARTUNG,HANS-PETER; KIESEIER,BERND C. |
| Matrix metalloproteinases (MMPs) comprise a large group of endoproteinases that degrade all protein components of the extracellular matrix. Functionally, MMPs contribute to several different physiological as well as pathological conditions. The number of newly described MMPs has increased in recent years, although current knowledge about their expression pattern in various tissues remains incomplete. Here we analyzed the relative mRNA expression of the most recently described MMPs _ MT5-MMP (MMP-24), MT6-MMP (MMP-25), MMP-27 and epilysin (MMP-28) _ in a broad selection of rat tissues using real time-PCR. MMP-24 mRNA was found to be widely expressed with predominance in the central nervous system. MMP-25 mRNA, in contrast, exhibited peak expression levels... |
| Tipo: Journal article |
Palavras-chave: Bone; CNS; Epilysin; Kidney; MT5-MMP; MT6-MMP; Testis. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602005000200016 |
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| Nualart,Francisco; Salazar,Katterine; Oyarce,Karina; Cisternas,Pedro; Jara,Nery; Silva-Álvarez,Carmen; Pastor,Patricia; Martínez,Fernando; García,Andrea; García-Robles,María de los Ángeles; Tapia,Juan Carlos. |
| Stem cells are considered a valuable cellular resource for tissue replacement therapies in most brain disorders. Stem cells have the ability to self-replicate and differentiate into numerous cell types, including neurons, oligodendrocytes and astrocytes. As a result, stem cells have been considered the "holy grail" of modern medical neuroscience. Despite their tremendous therapeutic potential, little is known about the mechanisms that regulate their differentiation. In this review, we analyze stem cells in embryonic and adult brains, and illustrate the differentiation pathways that give origin to most brain cells. We also evaluate the emergent role of the well known anti-oxidant, vitamin C, in stem cell differentiation. We believe that a complete... |
| Tipo: Journal article |
Palavras-chave: Stem cells; Radial glia; Vitamin C; SVCT2; Brain development; Tanycytes; Bergmann glia; Neurogenic niche; Type B cells; Neuroblast; Parkinson's disease; Alzheimer's disease; Amyotrophic lateral sclerosis. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602012000300006 |
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| BAEZA,MARCELO E; SANHUEZA,MARIO A; CIFUENTES,VÍCTOR H. |
| The secretion of proteinaceous toxins is a widespread characteristic in environmental and laboratory yeast isolates, a phenomenon called "killer system". The killer phenotype (K+) can be encoded by extrachromosomal genetic elements (EGEs) as double stranded DNA or RNA molecules (dsDNA, dsRNA) or in nuclear genes. The spectrum of action and the activity of killer toxins are influenced by temperature, salinity and pH of media. In the present work we determined the existence of K+ in a collection of S. cerevisiae and P. anómala yeasts isolated from environmental, industrial and clinical sources. The assays were performed in strains belonging to three yeast genera used as sensitive cells and under a wide range of pH and temperatures. Approximately 51 % of... |
| Tipo: Journal article |
Palavras-chave: Killer system; Mycotoxin; DsRNA. |
| Ano: 2008 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602008000200007 |
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| Roth,Alejandro D; Liazoghli,Dalinda; Perez De Arce,Felipe; Colman,David R. |
| Myelin sheaths present two distinct domains: compacted myelin spirals and flanking non-compacted cytoplasmic channels, where lipid and protein segregation is established by unknown mechanisms. Septins, a conserved family of membrane and cytoskeletal interacting GTPases, form intracellular diffusion barriers during cell division and neurite extension and are expressed in myelinating cells. Septins, particularly septin 7 (Sept7), the central constituent of septin polymers, are associated with the cytoplasmic channels of myelinating cells. Here we show that Schwann cells deprived of Sept7 fail to wrap around axons from dorsal root ganglion neurons and exhibit disorganization of the actin cytoskeleton. Likewise, Sept7 distribution is dependent on microfilament... |
| Tipo: Journal article |
Palavras-chave: Axon wrapping; Septins; Myelination; Schwann Cells. |
| Ano: 2013 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602013000300004 |
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| Marçal-Pessoa,Ana Flávia; Bassi-Branco,Carmen Lucia; Salvatierra,Cristiana dos Santos Barbosa; Stoppiglia,Luiz Fabrizio; Ignacio-Souza,Letícia Martins; Reis,Sílvia Regina de Lima; Veloso,Roberto Vilela; Reis,Marise Auxiliadora de Barros; Carneiro,Everardo Magalhães; Boschero,Antonio Carlos; Arantes,Vanessa Cristina; Latorraca,Márcia Queiroz. |
| ^len |
| Tipo: Journal article |
Palavras-chave: Connexin 36 Connexin 43 β -catenin Low protein diet Pregnancy Pancreatic islets Rat. |
| Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100003 |
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| VALENZUELA,CARLOS Y.. |
| Neutral evolution results from random recurrent mutation and genetic drift. A small part of random evolution, that which is related to protein or DNA polymorphisms, is the subject of the Neutral Theory of Evolution. One of the foundations of this theory is the demonstration that the mutation rate (m) is equal to the substitution rate. Since both rates are independent of population size, they are independent of drift, which is dependent upon population size. Neutralists have erroneously equated the substitution rate with the fixation rate, despite the fact that they are antithetical conceptions. The neutralists then applied the random walk stochastic model to justify alleles or bases that were fixated or eliminated. In this model, once the allele or base... |
| Tipo: Journal article |
Palavras-chave: Neutral evolution; Neutral theory; Misconceptions; Bases fixation; Elimination. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000300004 |
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| Ventura-Juncá,Patricio; Irarrázaval,Isabel; Rolle,Augusto J; Gutiérrez,Juan I; Moreno,Ricardo D; Santos,Manuel J. |
| The advent of in vitro fertilization (IVF) in animals and humans implies an extraordinary change in the environment where the beginning of a new organism takes place. In mammals fertilization occurs in the maternal oviduct, where there are unique conditions for guaranteeing the encounter of the gametes and the first stages of development of the embryo and thus its future. During this period a major epigenetic reprogramming takes place that is crucial for the normal fate of the embryo. This epigenetic reprogramming is very vulnerable to changes in environmental conditions such as the ones implied in IVF, including in vitro culture, nutrition, light, temperature, oxygen tension, embryo-maternal signaling, and the general absence of protection against foreign... |
| Tipo: Journal article |
Palavras-chave: In vitro fertilization (IVF) in mammals; Epigenetics; Developmental alterations; Bioethical implications. |
| Ano: 2015 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100068 |
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| MONTENEGRO,GLORIA; PORTALUPPI,MARIANA C; SALAS,FRANCISCO A; DÍAZ,MARÍA F. |
| An ethanol extract prepared from the gametophyte Chilean native moss Sphagnum magellanicum was dried out, weighed and dissolved in distilled water. This extract was then assayed for its antibacterial activity against the G(-) bacteria Azotobacter vinelandii, Erwinia carotovora subsp. carotovora, Enterobacter aerogenes, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Vibrio cholerae, and the G(+) bacteria Staphylococcus aureus subsp. aureus, and Streptococcus type b. The growth of the cultures of E. carotovora subsp. carotovora, and V. cholerae was inhibited at a concentration of 581mg/ml of extract, while the cultures of E. coli, S. typhi and Streptococcus type b were inhibited at a concentration of 1.16 mg/mL of extract. The concentration of... |
| Tipo: Journal article |
Palavras-chave: Sphagnum magellanicum; Phenolic compounds; Antibacterial activity; MIC. |
| Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602009000200012 |
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| WILLIAMS,ALAN J; TANNA,BHAVNA. |
| Ryanodine binds with high affinity and specificity to a class of Ca2+-release channels known as ryanodine receptors (RyR). The interaction with RyR results in a dramatic alteration in function with open probability (Po) increasing markedly and rates of ion translocation modified. We have investigated the features of ryanodine that govern the interaction of the ligand with RyR and the mechanisms underlying the subsequent alterations in function by monitoring the effects of congeners and derivatives of ryanodine (ryanoids) on individual RyR2 channels. While the interaction of all tested ryanoids results in an increased Po, the amplitude of the modified conductance state depends upon the structure of the ryanoid. We propose that different rates of cation... |
| Tipo: Journal article |
Palavras-chave: Calcium; Ca2+-release channel; Sarcoplasmic reticulum; Ryanodine; Single channel. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000400006 |
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| REPETTO,GABRIELA M.. |
| Genomic imprinting is a reversible phenomenon that affects the expression of genes depending on their parental origin. The best characterized human disorders resulting from an alteration of the imprinting process are Angelman and Prader-Willi syndromes. They are due to the lack of active maternal or paternal genes, respectively, from chromosome region 15q11q13. Most cases arise via interstitial deletions. We review evidence that other common cytogenetic alterations of this region, interstitial and supernumerary duplications, could be the reciprocal products of the deletions and are also affected by the imprinting phenomenon, given the predominance of maternally-derived duplications in patients ascertained due to developmental delays or autistic features. |
| Tipo: Journal article |
Palavras-chave: Chromosome 15; Chromosome 15 deletions/duplications; Genomic imprinting. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602001000200020 |
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| Registros recuperados: 992 | |
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