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Registros recuperados: 38 | |
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TOVAR BOHÓRQUEZ,MARIO OSWALDO; CONTRERAS BRAVO,LUISA FERNANDA; CALDAS,MARIA LEONOR; RODRÍGUEZ CAICEDO,DANIEL; HURTADO GIRALDO,HERNÁN. |
La visión es de importancia variable dependiendo de la relación de los peces con su hábitat, siendo clave en algunas especies y secundaria en otras. El objetivo de este estudio fue realizar una comparación entre el ojo de capitán de la sabana y trucha arco iris. La primera, nativa del altiplano cundiboyacence. La segunda es una especie introducida al país y con alta importancia en la piscicultura. Se obtuvieron cortes de ojo a 5 µm de espesor en ambas especies. Las dos presentan la estructura ocular típica de teleósteos conformada por una retina con ocho capas y dos membranas, células fotorreceptoras (conos y bastones), así como los otros tipos de células neuronales características (bipolares, horizontales, amacrinas y ganglionares), y un cristalino casi... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ojo; Retina; Morfometría; Trucha arco iris; Capitán de la sabana. |
Ano: 2008 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2008000200005 |
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MÁRQUEZ GARCÍA,Asarí; SALAZAR,Víctor; LIMA,Lucimey. |
RESUMEN La deficiencia de zinc en humanos produce disminución de antioxidantes, asociados a taurina, en la retina y se relaciona con adaptación anormal a la oscuridad, cataratas, ceguera y degeneración macular. Existe escasa evidencia acerca del efecto del zinc sobre el sistema de taurina en retina de mamíferos, por lo cual estudiamos el efecto del zinc sobre el transportador de taurina (TAUT) y los transportadores de zinc (ZnT-1 y 3) usando el quelante de zinc extracelular, ácido dietileno-triamino-penta-acético (DTPA), mediante inmunocitoquímica e inmunohistoquímica fluorescentes en células ganglionares (CG) y en las capas de la retina de ratas. Tres días después de la administración de DTPA (10μM) se utilizaron anticuerpos primarios y secundarios... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Retina; Taurina; Transportador de taurina; Transportadores de zinc; Zinc. |
Ano: 2017 |
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2017000200002 |
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Crivelaro,R.M.; Thiesen,R.; Aldrovani,M.; Lima,T.B.; Ortêncio,K.P.; Padua,I.R.M.; Duarte,J.M.B.; Laus,J.L.. |
ABSTRACT The aim of this study was to establish normal baseline ERG values of 23 anesthetized deer belonging to 8 neotropical species (Mazama americana, Mazama nemorivaga, Mazama gouazoubira, Mazama nana, Mazama bororo, Ozotocerus bezoarticus, Odocoileus virginianus and Blastocerus dichotomus). Only right eyes were studied. Chemical restraint was performed using xylazine associated with ketamine, IM, for M. americana, M. gouazoubira, M. nemorivaga, M. nana, M. bororo, O. bezoarticus and O. virginianus. A combination of tiletamine/zolazepam diluted in xylazine 2% was used for B. dichotomus individuals. After 20min of dark adaptation, electroretinograms were obtained using a handheld electroretinography (ERG) machine using the QuickRetCheck Protocol at three... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cervidae; Habitat; Retina; Wild animal; ERG. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352018000501505 |
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Morais,T.L.; Neves,C.A.; Borges,N.C; Lima,A.M.V; Silva,L.F.L; Castro,L.T.S; Espindola,S.O; Cunha,P.H.J. |
RESUMO No presente estudo, foram avaliados parâmetros oftalmológicos de 38 bovinos das raças Nelore (n= 19; grupo GN) e Gir (n= 19; grupo GG), machos, com idade média de 15 meses. Os exames oftalmológicos realizados foram teste lacrimal de Schirmer 1 (TLS-1), tonometria de aplanação, retinografia e biometria por ultrassonografia em modo B. Os resultados do TLS-1, tonometria de aplanação e biometria ocular foram avaliados por meio da análise de variância (ANOVA), e as médias comparadas pelo teste de Tukey. Para o exame de retinografia, foi realizada a análise descritiva das estruturas anatômicas. O TLS-1 e a tonometria não diferiram (P≥0,05) nas comparações entre os olhos e entre os grupos raciais. A retinografia permitiu a visualização do disco óptico, dos... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Oftalmologia; Retina; Schirmer; Tonometria; Ultrassonografia. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352019000100177 |
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ALBORNOZ,AMELINA; YÁÑEZ,JOSÉ M; FOERSTER,CLAUDIA; AGUIRRE,CELESTE; PEREIRO,LUISA; BURZIO,VERÓNICA; MORAGA,MAURICIO; REYES,ARIEL E; ANTONELLI,MARCELO. |
Protein kinase CK1 is a ser/thr protein kinase family which has been identified in the cytosol cell fraction, associated with membranes as well as in the nucleus. Several isoforms of this gene family have been described in various organisms: CK1á, CK1ß, CK1δ, CK1å and CK1γ. Over the last decade, several members of this family have been involved in development processes related to wnt and sonic hedgehog signalling pathways. However, there is no detailed temporal information on the CK1 family in embryonic stages, even though orthologous genes have been described in several different vertebrate species. In this study, we describe for the first time the cloning and detailed expression pattern of five CK1 zebrafish genes. Sequence analysis... |
Tipo: Journal article |
Palavras-chave: CK1; Casein Kinase 1; Expression pattern; Development; Zebrafish; Otic vesicles; Retina; Lens; Pectoral fin bud; Tegmentum; Myelencephalon; Telencephalon; Diencephalon; Mesencephalon; Rhombomeres. |
Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602007000200015 |
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Hong,S.; Hara,H.; Shimazawa,M.; Hyakkoku,K.; Kim,C.Y.; Seong,G.J.. |
Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g) for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6), a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6), a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Agmatine; Apoptosis; Ischemia; Neuroprotection; Retina. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2012000300005 |
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Sholl-Franco,A.; Araujo,E.G.. |
Cytokines are a heterogeneous group of molecules that have been associated with several functions in the nervous system, such as survival and differentiation of neuronal and glial cells. In the present study, we demonstrated that conditioned medium from spleen cells activated with concanavalin A increased neuritogenesis and survival of retinal cells, as measured by biochemical and morphological criteria. Our data showed that conditioned medium induced a five-fold increase in the amount of protein after 120 h in vitro. This effect was not inhibited by the blockade of voltage-dependent L-type calcium channels with 5.0 µM nifedipine. However, the use of an intracellular calcium chelator (15.0 µM BAPTA-AM) inhibited this effect. Our results support the idea... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cytokines; Growth factor; Neuroimmunology; Retina; Development. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997001100006 |
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Sternberg,C.; Benchimol,M.; Linden,R.. |
We examined the degeneration of post-mitotic ganglion cells in ex-vivo neonatal retinal explants following axon damage. Ultrastructural features of both apoptosis and autophagy were detected. Degenerating cells reacted with antibodies specific for activated caspase-3 or -9, consistent with the presence of caspase activity. Furthermore, peptidic inhibitors of caspase-9, -6 or -3 prevented cell death (100 µM Ac-LEDH-CHO, 50 µM Ac-VEID-CHO and 10 µM Z-DEVD-fmk, respectively). Interestingly, inhibition of autophagy by 7-10 mM 3-methyl-adenine increased the rate of cell death. Immunohistochemistry data, caspase activation and caspase inhibition data suggest that axotomy of neonatal retinal ganglion cells triggers the intrinsic apoptotic pathway, which, in turn,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Apoptosis; Autophagy; Caspases; Retina; Central nervous system. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010001000005 |
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Tanan,C.L.; Ventura,D.F.; de Souza,J.M.; Grotzner,S.R.; Mela,M.; Gouveia Jr.,A.; Oliveira-Ribeiro,C.A.. |
Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Methyl mercury; Horizontal cells; Electrophysiology; Hoplias malabaricus; Retina. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2006000700017 |
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Circadian organization means the way in which the entire circadian system above the cellular level is put together physically and the principles and rules that determine the interactions among its component parts which produce overt rhythms of physiology and behavior. Understanding this organization and its evolution is of practical importance as well as of basic interest. The first major problem that we face is the difficulty of making sense of the apparently great diversity that we observe in circadian organization of diverse vertebrates. Some of this diversity falls neatly into place along phylogenetic lines leading to firm generalizations: i) in all vertebrates there is a "circadian axis" consisting of the retinas, the pineal gland and the... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Circadian rhythms; Evolution; Vertebrates; Pineal; SCN; Retina; Melatonin. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000300003 |
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Sanches,G.; Ventura,A.L.M.. |
In the present study, we report that low concentrations of the glutamate ionotropic agonist kainate decreased the turnover of [3H]-phosphoinositides ([3H]-InsPs) induced by muscarinic receptors in the chick embryonic retina. When 100 µM carbachol was used, the estimated IC50 value for kainate was 0.2 µM and the maximal inhibition of ~50% was obtained with 1 µM or higher concentrations of the glutamatergic agonist. Our data also show that veratridine, a neurotoxin that increases the permeability of voltage-sensitive sodium channels, had no effect on [3H]-InsPs levels of the embryonic retina. However, 50 µM veratridine, but not 50 mM KCl, inhibited ~65% of the retinal response to carbachol. While carbachol increased [3H]-InsPs levels from 241.2 ± 38.0 to... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Muscarinic receptors; Phosphoinositides; Kainate; Sodium channels; Retina. |
Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1998000700009 |
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Linden,R.; Chiarini,L.B.. |
Programmed cell death in the form of apoptosis involves a network of metabolic events and may be triggered by a variety of stimuli in distinct cells. The nervous system contains several neuron and glial cell types, and developmental events are strongly dependent on selective cell interactions. Retinal explants have been used as a model to investigate apoptosis in nervous tissue. This preparation maintains the structural complexity and cell interactions similar to the retina in situ, and contains cells in all stages of development. We review the finding of nuclear exclusion of several transcription factors during apoptosis in retinal cells. The data reviewed in this paper suggest a link between apoptosis and a failure in the nucleo-cytoplasmic partition of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Programmed cell death; Retina; Neurogenesis; Development; Nuclear membrane. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000700003 |
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Pereira,S.P.F.; Araujo,E.G.. |
Neuronal cell death is an important phenomenon involving many biochemical pathways. This degenerative event has been studied to understand how the cells activate the mechanisms that lead to self-destruction. Target cells and afferent cells play a relevant role in the regulation of natural cell death. We studied the effect of veratridine (1.5, 3.0, 4.5 and 6.0 µM) on the survival of neonatal rat retinal ganglion cells in vitro. Veratridine (3.0 µM), a well-known depolarizing agent that opens the Na+ channel, promoted a two-fold increase in the survival of retinal ganglion cells kept in culture for 48 h. This effect was dose-dependent and was blocked by 1.0 µM tetrodotoxin (a classical voltage-dependent Na+ channel blocker) and 30.0 µM flunarizine (a Na+ and... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Veratridine; Retinal ganglion cells; Natural cell death; Development; Retina. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997001200014 |
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Registros recuperados: 38 | |
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