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Peptídeo C16 regula migração, invasão, invadopódios e suas moléculas-chave, bem como geração de espécies reativas de oxigênio em células tumorais prostáticas.; Laminin-derived peptide C16 regulates migration, invasion, invadopodia key-molecules, and ROS generation in human prostate cancer cells.

Santos, Lívia Caires dos
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 19/11/2014 PT
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36.61%
O câncer de próstata é o segundo câncer mais freqüentemente diagnosticado em homens. Durante o crescimento tumoral, as células neoplásicas interagem com a matriz extracelular (MEC). Analisamos o efeito de C16, peptídeo derivado da clivagem da MEC, sobre a migração, invasão e regulação dos invadopódios em células de câncer de próstata (DU145). Ensaios de migração e invasão demonstraram que C16 promoveu um aumento da atividade migratória e invasiva de células DU145 de maneira dose dependente. Demonstramos que o peptídeo estimula a fosforilação de Src. Ensaios de degradação em substrato fluorescente mostraram que C16 promoveu a formação de invadopódios de células DU145. O immunoblot nos revelou que este peptídeo também estimula a expressão de Tks4, Tks5, cortactina e MT1-MMP. C16 estimulou a produção de espécies reativas de oxigênio, importantes para o fenótipo invasivo das células tumorais. Nossos resultados sugerem que o peptídeo C16 regula migração, invasão, invadopódios e suas moléculas-chave e a geração de espécies reativas de oxigênio em células DU145.; Prostate cancer is the second most frequently diagnosed cancer in males. During tumor growth, neoplastic cells interact with the extracellular matrix (ECM) Our Laboratory has demonstrated that peptides derived from ECM cleavage are involved in migration...

Osteoblast Adhesion Dynamics: A Possible Role for ROS and LMW-PTP

Fernandes, Gustavo V. O.; Cavagis, Alexandre D. M.; Ferreira, Carmen V.; Olej, Beni; Leao, Mauricio de Souza; Yano, Claudia L.; Peppelenbosch, Maikel; Granjeiro, Jose Mauro; Zambuzzi, Willian F.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 1063-1069
ENG
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Reactive oxygen species (ROS) modulate a variety of intracellular events, but their role in osteoblast adhesion and spreading remains unclear. ROS is a very-known physiological modulators of Protein Tyrosine Phosphatases activities, mainly to low molecular weight protein tyrosine phosphatase (LMW-PTP) activity. As this biological mechanism is not clear in osteoblast adhesion, we decided to investigate ROS levels and phosphorylations of FAK and Src, identifying these proteins as potential substrates to LMW-PTP activity. Our results showed that during osteoblast adhesion/spreading (30min and 2h of seeding) the intracellular ROS content (hydrogen peroxide) is finely regulated by an effective anti-oxidant system [catalase and Superoxide Dismutase (SOD) activities were evaluated]. During the first 30min of adhesion, there was an increase in ROS production and a concomitant increase in focal adhesion kinase (FAK) activity after its phosphorylation at Tyrosine 397 (Y-397). Moreover, after 2h there was a decrease in ROS content and FAK phosphorylation. There was no significant change in LMW-PTP expression at 30min or 2h. In order to validate our hypothesis that LMW-PTP is able to control FAK activity by modulating its phosphorylation status...

Induction and determination of ROS and their effect on peroxisome dynamics

Pinho, Sónia Andreia de Almeida
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Dissertação de Mestrado
ENG
Relevância na Pesquisa
26.9%
Peroxissomas são organelos celulares de membrana simples, os quais têm importantes funções metabólicas, como por exemplo metabolismo de lípidos e ROS, sendo assim indispensáveis para a saúde e desenvolvimento humano. Os peroxissomas são organelos altamente flexíveis e dinâmicos que rapidamente se agregam, multiplicam e degradam em resposta a necessidades metabólicas. Em cultura celular, o stress oxidativo e outros estímulos externos (ex. factores de crescimento, ácidos gordos, despolimerização) têm mostrado induzir processos de crescimento (alongamento) e divisão de peroxissomas, os quais estão relacionados com a sua proliferação. Considerando que alguns dos componentes moleculares da maquinaria de crescimento e divisão têm sido identificados nos últimos anos, as vias de sinalização e regulação que medeiam a proliferação de peroxissomas são largamente desconhecidas. O objectivo desta dissertação de mestrado foi examinar o efeito de diferentes estímulos externos promotores de ROS na indução do crescimento/proliferação do compartimento peroxisomal. Foi seleccionado um sistema de cultura de células de mamífero que apresentam um compartimento peroxisomal dinâmico. Análises baseadas em fluorescência para a detecção da produção de ROS e alterações nos níveis de GSH intracelular foram estabelecidos. Estes procedimentos foram usados primeiro para esclarecer se o alongamento de peroxissomas observado após despolimerização de microtubulos (pelo nocodazole) é mediado por ROS. O alongamento de peroxissomas e a despolimerização dos microtubulos após tratamento com nocodazole foi monitorizado e quantificado por microscopia de imunofluorescência. O Nocodazole induziu um aumento dos níveis de ROS intracelular e apesar do pré tratamento com antioxidantes ter baixado os níveis de ROS...

Proto-oncogene c-ros codes for a molecule with structural features common to those of growth factor receptors and displays tissue specific and developmentally regulated expression.

Neckameyer, W S; Shibuya, M; Hsu, M T; Wang, L H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1986 EN
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A recombinant DNA clone containing cellular sequences homologous to the transforming sequence, v-ros, of avian sarcoma virus UR2 was isolated from a chicken genomic DNA library. Heteroduplex mapping and nucleotide sequencing reveal that the v-ros sequences are distributed in nine exons ranging from 65 to 204 nucleotides on cellular ros (c-ros) DNA over a range of 11 kilobases. Comparison of the deduced amino acid sequences of c-ros and v-ros shows two differences: v-ros contains a three-amino-acid insertion within the hydrophobic domain presumed to be involved in membrane association, and (ii) the carboxyl 12 amino acids of v-ros are completely different from those of the deduced c-ros sequence. The deduced amino acid sequence of c-ros bears striking structural features similar to those of insulin and epidermal growth factor receptors, including the presumed hydrophobic membrane binding domain, amino acids flanking the domain, and the distance between the domain and the catalytic region of the kinase activity. The expression of c-ros appears to be under a very stringent control. When tissues at various stages of chicken development were analyzed, only kidney was found to contain a significant level of c-ros RNA. The level of c-ros RNA in kidney tissue is most abundant in 7- to 14-day-old chickens. Finally...

Reactive Oxygen Species (Ros-Induced) Ros Release: A New Phenomenon Accompanying Induction of the Mitochondrial Permeability Transition in Cardiac Myocytes

Zorov, Dmitry B.; Filburn, Charles R.; Klotz, Lars-Oliver; Zweier, Jay L.; Sollott, Steven J.
Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 02/10/2000 EN
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We sought to understand the relationship between reactive oxygen species (ROS) and the mitochondrial permeability transition (MPT) in cardiac myocytes based on the observation of increased ROS production at sites of spontaneously deenergized mitochondria. We devised a new model enabling incremental ROS accumulation in individual mitochondria in isolated cardiac myocytes via photoactivation of tetramethylrhodamine derivatives, which also served to report the mitochondrial transmembrane potential, ΔΨ. This ROS accumulation reproducibly triggered abrupt (and sometimes reversible) mitochondrial depolarization. This phenomenon was ascribed to MPT induction because (a) bongkrekic acid prevented it and (b) mitochondria became permeable for calcein (∼620 daltons) concurrently with depolarization. These photodynamically produced “triggering” ROS caused the MPT induction, as the ROS scavenger Trolox prevented it. The time required for triggering ROS to induce the MPT was dependent on intrinsic cellular ROS-scavenging redox mechanisms, particularly glutathione. MPT induction caused by triggering ROS coincided with a burst of mitochondrial ROS generation, as measured by dichlorofluorescein fluorescence, which we have termed mitochondrial “ROS-induced ROS release” (RIRR). This MPT induction/RIRR phenomenon in cardiac myocytes often occurred synchronously and reversibly among long chains of adjacent mitochondria demonstrating apparent cooperativity. The observed link between MPT and RIRR could be a fundamental phenomenon in mitochondrial and cell biology.

ROS-GC interlocked Ca2+-sensor S100B protein signaling in cone photoreceptors: review

Sharma, Rameshwar K.; Makino, Clint L.; Hicks, David; Duda, Teresa
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
EN_US
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Photoreceptor rod outer segment membrane guanylate cyclase (ROS-GC) is central to visual transduction; it generates cyclic GMP, the second messenger of the photon signal. Photoexcited rhodopsin initiates a biochemical cascade that leads to a drop in the intracellular level of cyclic GMP and closure of cyclic nucleotide gated ion channels. Recovery of the photoresponse requires resynthesis of cyclic GMP, typically by a pair of ROS-GCs, 1 and 2. In rods, ROS-GCs exist as complexes with guanylate cyclase activating proteins (GCAPs), which are Ca2+-sensing elements. There is a light-induced fall in intracellular Ca2+. As Ca2+ dissociates from GCAPs in the 20–200 nM range, ROS-GC activity rises to quicken the photoresponse recovery. GCAPs then progressively turn down ROS-GC activity as Ca2+ and cyclic GMP levels return to baseline. To date, GCAPs mediate the only known mechanism of ROS-GC regulation in the photoreceptors. However, in mammalian cone outer segments, cone synapses and ON bipolar cells, another Ca2+ sensor protein, S100B, complexes with ROS-GC1 and senses the Ca2+ signal with a K1/2 of 400 nM. Unlike GCAPs, S100B stimulates ROS-GC activity when Ca2+ is bound. Thus, the ROS-GC system in cones functions as a Ca2+ bimodal switch; with rising intracellular Ca2+...

ROS as a middleware to Internet of Things

Hax, Vinicius Alves; Duarte Filho, Nelson Lopes; Botelho, Silvia Silva da Costa; Mendizabal, Odorico Machado
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
ENG
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This paper discusses the feasibility of using the framework Robot Operating System (ROS) as a basis for the development of a middleware in the Internet of Things (IoT) context. The main concepts regarding IoT and ROS are presented and followed by the evaluation criteria. Finally, case studies considering the ROS features and some common assumptions of IoT environments are analyzed.

The Production of Mitochondrial Reactive Oxygen Species at Steady-state Oxygen Concentrations: Implications for Oxygen Sensing.

Hoffman , David Leland ; Brookes, Paul S.
Fonte: Universidade de Rochester Publicador: Universidade de Rochester
Tipo: Tese de Doutorado
ENG
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Thesis (Ph.D.)--University of Rochester. School of Medicine and Dentistry. Dept. of Biochemistry and Biophysics, 2009.; The mitochondrial production of reactive oxygen species (mtROS) at low [O2] is a well-established phenomenon in cellular oxygen sensing. The mechanism by which mitochondria make ROS at low [O2] is thought to occur through the inhibition of cytochrome c oxidase (complex IV), the terminal enzyme within the electron transport chain (ETC). Inhibition of complex IV, brought about by O2 limitation, leads to the buildup of electrons within the ETC, and subsequent “leakage” of electrons from ubiquinone cytochrome c oxidoreductase (complex III) on to O2. This leakage results in the formation of the superoxide radical (O2•-). When this radical species is dismuted to the uncharged H2O2, it is able to cross membranes, entering the cytosol to function as a signal. Given the nature of this mechanism, this generation of mtROS is hypothesized to be mitochondria autonomous, and should therefore occur in isolated mitochondria. In addition, this hypoxic ROS generation is somewhat paradoxical, since the primary substrate for the production of ROS, O2, is limited in hypoxia. Because of both this specific mechanism of ROS generation...

Ceramic raw materials from the State of Maranh?o, Brazil. Part 1: chemical and mineralogical characterization and technological properties of clays from S?o Luis, Ros?rio, Pinheiro and Mirinzal

MERCURY, Jos? Manuel Rivas; CORREIA, Gricirene Sousa; VASCONCELOS, Nazar? do Socorro Lemos Silva; CABRAL J?NIOR, Alu?sio Alves; ANG?LICA, R?mulo Sim?es
Fonte: Universidade Federal do Pará Publicador: Universidade Federal do Pará
Tipo: Artigo de Revista Científica
ENG
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Nesse trabalho, foram caracterizadas algumas argilas coletadas nos munic?pios de S?o Lu?s, Ros?rio, Pinheiro e Mirinzal. A caracteriza??o foi realizada atrav?s dos ensaios de difra??o de raios X, massa espec?fica real, capacidade de troca de c?tions (CTC), ?rea superficial, distribui??o granulom?trica, an?lise qu?mica, an?lise t?rmica (TG-DTA) e limites de Atterberg. Ensaios tecnol?gicos de retra??o linear, antes e ap?s a queima, absor??o de ?gua e tens?o de ruptura a flex?o, em tr?s pontos, foram realizados em corpos de prova prensados uniaxialmente a 20 MPa e tratados termicamente em 850, 950, 1050, 1150 e 1250?C. Os resultados obtidos permitiram identificar duas argilas de queima branca, constitu?das de quartzo, caolim, feldspato e anat?sio, com excelentes propriedades para uso em cer?mica branca. As restantes s?o queima vermelha e possuem composi??o mineral?gica de quartzo, caolim, feldspato, montmorilonita, hematita e goetita. Estas ?ltimas apresentaram valores moderados de plasticidade e s?o adequadas para aplica??es em cer?mica vermelha.; ABSTRACT: This work involved the characterization of clays collected in the municipalities of S?o Luis, Ros?rio, Pinheiro and Mirinzal (state of Maranh?o, Brazil), based on specific mass, specific surface area...

Transient Receptor Potential Vanilloid 1 (TRPV1) activation induces autophagy in thymocytes through ROS-regulated AMPK and Atg4C pathways.

Farfariello, Valerio
Fonte: La Sapienza Universidade de Roma Publicador: La Sapienza Universidade de Roma
Tipo: Tese de Doutorado
EN
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Autophagy is a highly conserved process involved in lymphocyte development and differentiation. Herein, we demonstrated for the first time that triggering of Transient Receptor Potential Vanilloid 1 (TRPV1) by the specific agonist capsaicin (CPS) induces autophagy in mouse thymocytes. TRPV1-dependent autophagy required calcium influx and ROS generation resulting in AMP-activated kinase (AMPK) activation. CPS specifically increased autophagy related 4C (Atg4C) mRNA expression and induced oxidation of Atg4C protein by ROS generation. TRPV1-triggered autophagy was Atg6/Beclin-1-dependent, as demonstrated by the use of Beclin-1+/- transgenic mice, and involved ROS- and AMPK-mediated up-regulation of Beclin-1 expression. Autophagy is activated as pro-survival process since its inhibition triggered apoptosis of thymocytes: this effect was accompanied by down-regulation of Atg4C, Bcl-XL and immunity-related GTPase family M (Irgm1) mRNA expression, decreased Bcl-XL and Beclin-1 protein levels and caspase-3 activation, suggesting the existence of a molecular interplay between autophagic and apoptotic programs. TRPV1 activation by CPS altered the expression of CD4 and CD8α antigens, inducing the development of a double positive subpopulation expressing lower levels of both receptors (DPdull)...

The transcription factor p53 contributes to the regulation of neurogenesis and oligodendrogenesis in embryonic neural progenitor cells by fine-tuning intracellular ROS levels; Der Transkriptionfaktor p53 reguliert ROS-Homöostase, und dadurch Neurogenese und Oligodendrogenese, in embryonalen neuronalen Stammzellen

Forsberg, Kirsi
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
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The transcription factor p53 has recognized roles in cell cycle arrest, apoptosis, DNA damage response and cellular redox regulation. In situ hybridization has demonstrated high expression level of p53 mRNA in all embryonic mouse tissues up to the embryonic day 10.5, after which p53 expression becomes more restricted being profound only in the germinal zones of the developing brain, such as in the ventricular (VZ) and sub-ventricular zone (SVZ) and in the ganglionic eminence (GE) of the developing brain. Nevertheless, in spite of the fact that 16-24% of p53-/- mouse embryos die from defective neural tube closure in the midbrain-hindbrain boundary, which suggests a role for p53 in brain development, the conventional view is that p53 is dispensable during CNS development. In this work I have set out to explore explanations for p53 expression in the germinal zones of the embryonic telencephalon. Since a recent work attributed a regulatory function to reactive oxygen species (ROS) in the normal homeostasis of neural stem cells (NSC) and since some of the target genes of p53 possess antioxidant properties, I set out in this dissertation work to explore the hypothesis that p53 regulates the abundance of intracellular ROS in NSCs and thereby their proliferation/differentiation decisions in the embryonic and postnatal germinal zones. To study this...

Function and Regulation of Na+/ H+ Exchanger in Dendritic Cells; Funktion und Regulation des Na+/H+ Austauscher in Dendritischen Zellen

Pasham, Venkanna
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
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Dendritic cells (DCs) are specialised antigen presenting cells, linking innate and adaptive immunity. They are stimulated by bacterial lipopolysaccharides (LPS), which trigger the formation of reactive oxygen species (ROS). In macrophages, ROS formation is paralleled by the activation of the Na+/H+ exchanger, a transporter involved in the regulation of cytosolic pH and cell volume. The present study was undertaken to unravel the possible role of Na+/H+ exchanger in the activation of DCs. In the first step, using quantitative real time PCR analysis the expression of Na+/H+ exchanger (NHE) isoforms in bone marrow-derived mouse DCs was analysed. The expression of NHE1 was highest among the various isoforms known to be localised in the cell membrane, so the study focussed on the functional significance of NHE1 isoform. Exposure of DCs to LPS, within 4 hours led to a gradual cytosolic acidification paralleled by a transient time and dose dependent increase of Na+/H+ exchanger activity. Moreover, LPS increased forward scatter in FACS, reflecting increase of cell volume, enhanced ROS formation, decreased apoptosis and stimulated release of TNF-alpha. An NHE1 inhibitor cariporide (10 µM) significantly blunted the effects of LPS on Na+/H+ exchanger activity...

[A S.M. en vista de la consulta del Asesor general de la Orden de Montesa sobre lo c??mo se ha de proceder con D. Dionisio Ros tras haberse declarado que toca a la religi??n el conocimiento de su causa : carta / Antonio de la Riva Herrera]

Ib????ez de la Riva Herrera, Antonio, Arzobispo de Zaragoza; Carlos II, Rey de Espa??a, 1661-1700; Ros, Dionisio
Fonte: Madrid Publicador: Madrid
Tipo: Livro
SPA
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Enc. Perg.; Incipit: "Se??or. Con papel de Dn. Juan de Angulo de 22 del corr[ien]te, se sirue V. Mg. mandar remitir la consulta (que vuelbe adjunta) del Asesor Genl. de la Orden de Montesa sobre la dependencia de Dn. Dionisio Ros..." (fol. 197r); Explicit: "... Y en quanto a que se suelen poner a los caualleros de las Ordenes militares en semejantes Conuentos se estila en causas que no son sobre delitos capitales. V. Mg. resolvera lo que fuere seruido. M[adri]d y Ag[os]to 23 de 1692 (fol. 198v)

Transforming properties and substrate specificities of the protein tyrosine kinase oncogenes ros and src and their recombinants.

Jong, S M; Zong, C S; Dorai, T; Wang, L H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1992 EN
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To determine the sequences of the oncogenes src (encoded by Rous sarcoma virus [RSV]) and ros (encoded by UR2) that are responsible for causing different transformation phenotypes and to correlate those sequences with differences in substrate recognition, we constructed recombinants of the two transforming protein tyrosine kinases (PTKs) and studied their biological and biochemical properties. A recombinant with a 5' end from src and a 3' end from ros, called SRC x ROS, transformed chicken embryo fibroblasts (CEF) to a spindle shape morphology, mimicking that of UR2. Neither of the two reverse constructs, ROS x SRC I and ROS x SRC II, could transform CEF. However, a transforming variant of ROS x SRC II appeared during passages of the transfected cells and was called ROS x SRC (R). ROS x SRC (R) contains a 16-amino-acid deletion that includes the 3' half of the transmembrane domain of ros. Unlike RSV, ROS x SRC (R) also transformed CEF to an elongated shape similar to that of UR2. We conclude that distinct phenotypic changes of RSV- and UR2-infected cells do not depend solely on the kinase domains of their oncogenes. We next examined cellular proteins phosphorylated by the tyrosine kinases of UR2, RSV, and their recombinants as well as a number of other avian sarcoma viruses including Fujinami sarcoma virus Y73...

Role of gag sequence in the biochemical properties and transforming activity of the avian sarcoma virus UR2-encoded gag-ros fusion protein.

Jong, S M; Wang, L H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1990 EN
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The transforming protein P68gag-ros of avian sarcoma virus UR2 is a transmembrane tyrosine protein kinase molecule with the gag portion protruding extracellularly. To investigate the role of the gag moiety in the biochemical properties and biological functions of the P68gag-ros fusion protein, retroviruses containing the ros coding sequence of UR2 were constructed and analyzed. The gag-free ros protein was expressed from one of the mutant retroviruses at a level 10 to 50% of that of the wild-type UR2. However, the gag-free ros-containing viruses were not able to either transform chicken embryo fibroblasts or induce tumors in chickens. The specific tyrosine protein kinase activity of gag-free ros protein is about 10- to 20-fold reduced as judged by in vitro autophosphorylation. The gag-free ros protein is still capable of associating with membrane fractions including the plasma membrane, indicating that sequences essential for recognition and binding membranes must be located within ros. Upon passages of the gag-free mutants, transforming and tumorigenic variants occasionally emerged. The variants were found to have regained the gag sequence fused to the 5' end of the ros, apparently via recombination with the helper virus or through intramolecular recombination between ros and upstream gag sequences in the same virus construct. All three variants analyzed code for gag-ros fusion protein larger than 68 kDa. The gag-ros recombination junction of one of the transforming variants was sequenced and found to consist of a p19-p10-p27-ros fusion sequence. We conclude that the gag sequence is essential for the transforming activity of P68gag-ros but is not important for its membrane association.

RAC1 activity and intracellular ROS modulate the migratory potential of MCF-7 cells through a NADPH oxidase and NF kappa B-dependent mechanism

Santibáñez, Juan Francisco; Smith, Patricio C.; Martínez, Jorge; Cáceres, Mónica; Tobar, Nicolás
Fonte: Elsevier Inc. Publicador: Elsevier Inc.
Tipo: Artículo de revista
EN
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36.53%
modulate the migratory properties in MCF-7 and T47D human mammary cell lines. We also described that the NFjB pathway exerts a downstream control on the expression of the ROS-dependent cellular migratory potential. These results emphasize the importance of redox balance in the acquisition of malignancy and support previous data sustaining that an oxidative environment predisposes cells to activate signal-transduction pathways actively involved in cellular oncogenesis. Our data also provides evidence that NADPH oxidase could constitute the main source of intracellular ROS in response to changes in Rac1 activity. We suggest that Rac1 plays a role in cellular migration not only limited to its known function in reorganization of the actin cytoskeleton, but also as part of the intracellular machinery that controls the redox balance.; This work received financial support from FONDECYT (Grant 1040734).

Células troncales mesenquimáticas humanas (hMSC) eliminan eficientemente las especies reactivas de oxígeno (ROS) y de nitrógeno (RNS)

Valle Prieto, María Araceli
Fonte: Universidad de Chile; CyberDocs Publicador: Universidad de Chile; CyberDocs
Tipo: Tesis
ES
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Tesis presentada a la Universidad de Chile para optar al grado académico de Doctor en Farmacología; El trasplante de células troncales mesenquimáticas humanas (hMSC) derivadas de médula ósea ha mostrado ser terapéutico en patologías como osteogénesis imperfecta, reacción del injerto contra huésped e infarto agudo al miocardio. Además, ha permitido recuperar las funciones motoras y sensoriales en animales con infarto cerebral, la producción de insulina en animales diabéticos y evitar la muerte neuronal en animales con enfermedad de Parkinson. En todas estas patologías el daño tisular se vincula a estrés oxidativo (EO). A la fecha, los mecanismos propuestos para explicar los efectos terapéuticos de las MSC son: i) diferenciación a células del parénquima, ii) producción de factores tróficos que promueven proliferación y diferenciación de progenitores locales, iii) neovascularización, iv) inmunomodulación. Nosotros proponemos que las hMSC además actuarían como “atrapadores” de especies reactivas de oxígeno (ROS) y/o de nitrógeno (RNS), protegiendo así a las células del parénquima del daño oxidativo. Para evaluar esta hipótesis hemos caracterizado a las hMSC con respecto a su capacidad de manejar el EO. Primero...

Implementación de middleware ros para robot de servicio

Hevia Koch, Pablo Alejandro
Fonte: Universidad de Chile Publicador: Universidad de Chile
Tipo: Tesis
ES
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Ingeniero Civil Electricista; El objetivo del presente trabajo de memoria consiste en implementar el middleware ROS en el robot de servicio Bender, así como implementar un sistema de navegación con soporte para SLAM online, e integrar dicho sistema junto con los módulos preexistentes del robot, al tiempo de actualizarlos a una nueva versión de URBI. Este proyecto es parte del trabajo de mejora continua realizado con el robot Bender, del Laboratorio de Robótica del Departamento de Ingeniería Eléctrica de la Facultad de Ciencias Físicas y Matemáticas de la Universidad de Chile y enmarcado dentro de la participación de este robot en el campeonato mundial de robótica Robocup, en su categoría Robocup@Home. Tras una presentación del contexto y antecedentes respecto a las características del middleware, se procedió a implementar un sistema de navegación en base al middleware ROS utilizando el algoritmo de SLAM Online GMapping. Para esto, se implementan diversos módulos ROS: control de la base robótica, publicación de odometría, manejo de marcos de referencia, generación de mapas de costos, módulo SLAM, lecturas del sensor láser, planificador de rutas local y global, teleoperación, servidor de mapas de entorno y localización. Implementados los módulos de navegación en ROS...

Natural triterpenic diols promote apoptosis in astrocytoma cells through ROS-mediated mitochondrial depolarization and JNK activation

Martín, Rubén; Ibeas, Elvira; Carvalho-Tavares, Juliana; Hernández, Marita; Ruiz-Gutiérrez, Valentina; Nieto, María Luisa
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artículo Formato: 877431 bytes; application/pdf
ENG
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[Background]: Triterpene alcohols and acids are multifunctional compounds widely distributed throughout the plant kingdom that exhibit a variety of beneficial health properties, being synthetic analogs of oleanolic acid under clinical evaluation as anti-tumoral therapeutic agents. However, the antineoplastic activity of two natural occuring triterpenoid alcohols extracted from olive oil, erythrodiol (an intermediate from oleanolic acid), and its isomer, uvaol, has barely been reported, particularly on brain cancer cells. Astrocytomas are among the most common and aggressive type of primary malignant tumors in the neurological system lacking effective treatments, and in this study, we addressed the effect of these two triterpenic diols on the human 1321N1 astrocytoma cell line.; [Principal Findings]: Erythrodiol and uvaol effectively affected cell proliferation, as well as cell cycle phases and induced 1321N1 cell death. Both triterpenes successfully modulated the apoptotic response, promoting nuclear condensation and fragmentation. They caused retraction and rounding of cultured cells, which lost adherence from their supports, while F-actin and vimentin filaments disappeared as an organized cytoplasmic network. At molecular level, changes in the expression of surface proteins associated with adhesion or death processes were also observed. Moreover...

Miscel·lània història

Dalmases i Ros, Pau Ignasi de,
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Llibres electrònics; info:eu-repo/semantics/book Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf
Publicado em ]//[17 SPA
Relevância na Pesquisa
36.42%
Escrit entre 1675 i 1725; Localització: Barcelona, Biblioteca de Catalunya, ms. 618; Diverses mans, entre elles les de Pau Ignasi de Dalmases i Ros, i algunes petites esmenes; Anotacions al marge i text cancel·lat al contrapla posterior; Data aprox. deduïda del context i dels documents; F. 11-12, 26, 32, 34, 38, 36, 38, 40. 42, 44, 46, 48-49, 149-214, 216, 218, 220, 222, 224, 226, 228, 230, 232 i 234 en blanc; Diverses foliacions originals en tinta; El text dels f. 236-243 és capicuat; Col·lecció miscel·lània de textos que Pau Ignasi Dalmases féu copiar literalment dels originals escampats en diversos arxius i biblioteques catalanes, la majoria vinculades a la confecció dels "Anales de Catalun"