906 resultados para In Situ Hybridization, Fluorescence


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Se han utilizado los resultados de 144 lances ejecutados en el transcurso del Crucero 9803-05. Se compararon los histogramas de TS y los de tallas en búsqueda de correlación entre ambas a fin de determinar el factor b20 de la Ecuación de Fuerza de Blanco (20 log (LT,cm) + b20). Se han determinado nuevas ecuaciones de TS para anchoveta (38 y 120 kHz), sardina (120 kHz), jurel (38 kHz) y caballa (38 y 120 kHz). Se deberá continuar con estas mediciones puesto que un cambio en las propuestas reflectivas de los peces puede afectar la correcta obtención de los estimados de biomasa.

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BACKGROUND: The exceptionally diverse species flocks of cichlid fishes in East Africa are prime examples of parallel adaptive radiations. About 80% of East Africa's more than 1 800 endemic cichlid species, and all species of the flocks of Lakes Victoria and Malawi, belong to a particularly rapidly evolving lineage, the haplochromines. One characteristic feature of the haplochromines is their possession of egg-dummies on the males' anal fins. These egg-spots mimic real eggs and play an important role in the mating system of these maternal mouthbrooding fish. RESULTS: Here, we show that the egg-spots of haplochromines are made up of yellow pigment cells, xanthophores, and that a gene coding for a type III receptor tyrosine kinase, colony-stimulating factor 1 receptor a (csf1ra), is expressed in egg-spot tissue. Molecular evolutionary analyses reveal that the extracellular ligand-binding and receptor-interacting domain of csf1ra underwent adaptive sequence evolution in the ancestral lineage of the haplochromines, coinciding with the emergence of egg-dummies. We also find that csf1ra is expressed in the egg-dummies of a distantly related cichlid species, the ectodine cichlid Ophthalmotilapia ventralis, in which markings with similar functions evolved on the pelvic fin in convergence to those of the haplochromines. CONCLUSION: We conclude that modifications of existing signal transduction mechanisms might have evolved in the haplochromine lineage in association with the origination of anal fin egg-dummies. That positive selection has acted during the evolution of a color gene that seems to be involved in the morphogenesis of a sexually selected trait, the egg-dummies, highlights the importance of further investigations of the comparative genomic basis of the phenotypic diversification of cichlid fishes.

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Se efectuaron mediciones de TS (Fuerza de Blanco, Target Strenght) durante los 108 lances de comprobación de ecotrazos realizados por el BIC Humboldt en el marco del Crucero 9808-09 de Evaluación Hidroacústica de Recursos Pelágicos. Se consideran para el análisis únicamente aquellos lances donde más del 90% de la captura perteneció a una sola especie. Los factores b20 de la ecuación de TS (TS=20 log L - b20) que han sido determinados, las cuales deberán ser considerados como provisionales, son las siguientes: Pez cinta (Trichiurus lepturus) = 70,95 (120 kHz); Vinciguerria o pez linterna (Vinciguerria lucetia pacifici) = 83,29 (120 kHz); Samasa (Anchoa nasus) = 86,57 (120 kHz); Caballa (Scomber japonicus) = 83,09 (120 kHz); Pez cinta (Trichiurus lepturus) = 71,41 (38 kHz); y Vinciguerria o pez linterna (Vinciguerria lucetia pacifici)= 82,04 (38kHz).

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Se realizaron mediciones de la Fuerza de Blanco (TS) del krill (Euphausia superba) durante los 29 lances efectuados en el Crucero de Evaluación Hidroacústica utilizando la ecosonda SIMRAD EK 500 a bordo del BIC Humboldt entre los días 12 y 24 de enero de 1998 a lo largo del Estrecho de Bransfield y alrededores de la Isla Elefante. Se derivaron los valores de b20 a partir de le ecuación de TS de FOOTE (1990), de las longitudes promedios de los individuos capturados durante cada uno de los lances y de las tablas de TS generadas por la ecosonda, determinándose una ecuación de TS para el krill en un rango de longitud comprendido entre 2,1 y 5,3 cm de la siguiente forma: TS = 20 log L - 89,26. Se discute el posible sesgo de la ecuación debido, entre otros aspectos a que no se consideraron los estadíos sexuales del krill.

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Se efectuaron mediciones de TS (Fuerza de Blanco: Target Strength) durante los 100 lances de comprobación de ecotrazos realizados por el BIC José Olaya Balandra durante el Crucero 9811-12 de Evaluación Hidroacústica de Recursos Pelágicos. Se consideraron para el análisis únicamente aquellos lances donde más del 90% de la captura perteneció a una determinada especie y que, además, se haya observado en ellos una adecuada correlación entre los histogramas de tallas y de TS. Los factores b20 de la ecuación de TS (TS = 20 log L - b20) que han sido determinados, las cuales serán consideradas como provisionales, corresponden a anchoveta (2) y a bregmaceros (1). Estas son las siguientes: anchoveta, b20 = 81, 8 (para ejemplares entre 6 y 8,5 cm); anchoveta, b20 = 78,5 (para ejemplares entre 11,5 y 14,5 cm); bregmaceros, b20 = 80,25 (para ejemplares entre 5,5 y 8 cm).

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Se efectuaron mediciones de TS (Fuerza de Blanco: Target Strength) durante los 136 lances de comprobación de ecotrazos realizados por el BIC José Olaya Balandra durante el Crucero 9902-03 de Evaluación Hidroacústica de Recursos Pelágicos. Se consideraron para el análisis únicamente aquellos lances donde más del 90% de la captura perteneció a una especie y que, además, se haya observado en ellos una adecuada correlación entre los histogramas de tallas y de TS. Los factores b20 de la ecuación de TS (TS=20 log L - b20) que han sido determinados, las cuales serán consideradas como provisionales, corresponden a anchoveta (2) y a pota (1). Estas son las siguientes: anchoveta a 120 kHz, b20=82,2 (para ejemplares entre 5,5 y 9,5 cm); anchoveta 38 kHz, b20=81,2 (para ejemplares entre 5,5 y 10,5 cm); pota a 38 kHz, b20=87,2 (para ejemplares entre 12 y 24 cm de longitud de manto).

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We performed a case-control study to determine the association of BK plasma viremia with hemorrhagic cystitis (HC) in hematopoietic cell transplant (HCT) recipients. Thirty cases of HC (14 of which occurred after platelet engraftment with documented BK viruria [BK-HC]) were compared with matched controls. Weekly plasma samples were tested for BK virus DNA by polymerase chain reaction (PCR). BK viremia detected before or during the disease was independently associated with HC (adjusted odds ratio = 30, P < .001); BK viremia was even important before clinical symptoms of HC occurred (odds ratio = 11, P < .001). Cases of HC and BK-HC had a significantly higher peak of BK plasma viral load than controls. BK virus was detected by in situ hybridization in bladder biopsies of 2 cases with severe HC and long-lasting BK viremia. BK virus seems to play a role in the development of HC and quantitative detection of BK DNA in plasma appears to be a marker of BK virus disease in HCT recipients.

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Purpose Downregulation of TRPM1 mRNA, a transient receptor potential cation channel, has been identified in highly metastatic cutaneous melanoma cell lines. TRPM1 mRNA expression is inversely correlated with skin melanoma metastases. Recent evidence has demonstrated that the tumor suppressive activity of TRPM1 is due to miR211 situated in intron 6 of TRPM1. As we have previously identified a downregulation of TRPM1 mRNA expression in conjunctival melanoma, we decided to assess miR211 expression and its potential target gene IGF2R and KCNMA1 in conjunctival melanocytic proliferations. As MITF has been shown to regulate both TRPM1 and mir211 expression, we also assessed MITF expression in our series. Methods Expression of miR211 was assessed by in situ hybridization in 14 conjunctival naevi and 14 conjunctival melanoma. Integrity of miRNA in tissues was evaluated in each sample with the preservation of miR126 expression in endothelial cells. Protein expression of MITF, IGF2R and KCNMA1 was assessed by immunohistochemistry. Statistical analysis was performed with JUMP 8,0 software. In situ hybridization and immunohistochemistry were assessed independently by two observers. Results There were 7 subepithelial nevi and 7 compound nevi. There were 5 female and 9 male. The population mean age was 48.7 ± 6.4 years (SEM). miR211 was found in 11 nevi (79%). MITF was expressed in all the nevi. IGF2R was found in 13 nevi. KCNMA1 was found in 57% of the nevi.The melanoma group was composed of 9 females and 5 males with a mean age of 67 ± 4.8 years (SEM). Using the recent TNM classification, 5 tumors were belonging to the T1, 3 to theT2 and 6 to the T3 categories. miR211 was found in 5 melanoma (36%). There was a significant downregulation of miR211 in the melanoma compared to the nevi (p=0,0219). MITF was found in 13 melanoma (93%). IGF2R and KCNMA1 were respectively found in 71% and 77% of the melanoma. There was no significant differential expression of MITF, KCNMA1 and IGF2R between the nevi and the melanoma as well as no association between miR211 expression and protein expression of two potential target genes Conclusions In vivo miR211 is significantly reduced in conjunctival melanoma compared to conjunctival nevi. No correlation between mir211 expression and two potential target genes KCNMA1 and IGF2R was observed.

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By using an in vitro model of antibody-mediated demyelination, we investigated the relationship between tumor necrosis factor-alpha (TNF-alpha) and heat shock protein (HSP) induction with respect to oligodendrocyte survival. Differentiated aggregate cultures of rat telencephalon were subjected to demyelination by exposure to antibodies against myelin oligodendrocyte glycoprotein (MOG) and complement. Cultures were analyzed 48 hr after exposure. Myelin basic protein (MBP) expression was greatly decreased, but no evidence was found for either necrosis or apoptosis. TNF-alpha was significantly up-regulated. It was localized predominantly in neurons and to a lesser extent in astrocytes and oligodendrocytes, and it was not detectable in microglial cells. Among the different HSPs examined, HSP32 and alphaB-crystallin were up-regulated; they may confer protection from oxidative stress and from apoptotic death, respectively. These results suggest that TNF-alpha, often regarded as a promoter of oligodendroglial death, could alternatively mediate a protective pathway through alphaB-crystallin up-regulation.

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The corpus callosum (CC) plays a crucial role in interhemispheric communication. It has been shown that CC formation relies on the guidepost cells located in the midline region that include glutamatergic and GABAergic neurons as well as glial cells. However, the origin of these guidepost GABAergic neurons and their precise function in callosal axon pathfinding remain to be investigated. Here, we show that two distinct GABAergic neuronal subpopulations converge toward the midline prior to the arrival of callosal axons. Using in vivo and ex vivo fate mapping we show that CC GABAergic neurons originate in the caudal and medial ganglionic eminences (CGE and MGE) but not in the lateral ganglionic eminence (LGE). Time lapse imaging on organotypic slices and in vivo analyses further revealed that CC GABAergic neurons contribute to the normal navigation of callosal axons. The use of Nkx2.1 knockout (KO) mice confirmed a role of these neurons in the maintenance of proper behavior of callosal axons while growing through the CC. Indeed, using in vitro transplantation assays, we demonstrated that both MGE- and CGE-derived GABAergic neurons exert an attractive activity on callosal axons. Furthermore, by combining a sensitive RT-PCR technique with in situ hybridization, we demonstrate that CC neurons express multiple short and long range guidance cues. This study strongly suggests that MGE- and CGE-derived interneurons may guide CC axons by multiple guidance mechanisms and signaling pathways. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 73: 647-672, 2013.

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The in situ hybridization Allen Mouse Brain Atlas was mined for proteases expressed in the somatosensory cerebral cortex. Among the 480 genes coding for protease/peptidases, only four were found enriched in cortical interneurons: Reln coding for reelin; Adamts8 and Adamts15 belonging to the class of metzincin proteases involved in reshaping the perineuronal net (PNN) and Mme encoding for Neprilysin, the enzyme degrading amyloid β-peptides. The pattern of expression of metalloproteases (MPs) was analyzed by single-cell reverse transcriptase multiplex PCR after patch clamp and was compared with the expression of 10 canonical interneurons markers and 12 additional genes from the Allen Atlas. Clustering of these genes by K-means algorithm displays five distinct clusters. Among these five clusters, two fast-spiking interneuron clusters expressing the calcium-binding protein Pvalb were identified, one co-expressing Pvalb with Sst (PV-Sst) and another co-expressing Pvalb with three metallopeptidases Adamts8, Adamts15 and Mme (PV-MP). By using Wisteria floribunda agglutinin, a specific marker for PNN, PV-MP interneurons were found surrounded by PNN, whereas the ones expressing Sst, PV-Sst, were not.

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Islet-brain 1 (IB1) was recently identified as a DNA-binding protein of the GLUT2 gene promoter. The mouse IB1 is the rat and human homologue of the Jun-interacting protein 1 (JIP-1) which has been recognized as a key player in the regulation of c-Jun amino-terminal kinase (JNK) mitogen-activated protein kinase (MAPK) pathways. JIP-1 is involved in the control of apoptosis and may play a role in brain development and aging. Here, IB1 was studied in adult and developing mouse brain tissue by in situ hybridization, Northern and Western blot analysis at cellular and subcellular levels, as well as by immunocytochemistry in brain sections and cell cultures. IB1 expression was localized in the synaptic regions of the olfactory bulb, retina, cerebral and cerebellar cortex and hippocampus in the adult mouse brain. IB1 was also detected in a restricted number of axons, as in the mossy fibres from dentate gyrus in the hippocampus, and was found in soma, dendrites and axons of cerebellar Purkinje cells. After birth, IB1 expression peaks at postnatal day 15. IB1 was located in axonal and dendritic growth cones in primary telencephalon cells. By biochemical and subcellular fractionation of neuronal cells, IB1 was detected both in the cytosolic and membrane fractions. Taken together with previous data, the restricted neuronal expression of IB1 in developing and adult brain and its prominent localization in synapses suggest that the protein may be critical for cell signalling in developing and mature nerve terminals.

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To determine self‐consistently the time evolution of particle size and their number density in situ multi‐angle polarization‐sensitive laser light scattering was used. Cross‐polarization intensities (incident and scattered light intensities with opposite polarization) measured at 135° and ex situ transmission electronic microscopy analysis demonstrate the existence of nonspherical agglomerates during the early phase of agglomeration. Later in the particle time development both techniques reveal spherical particles again. The presence of strong cross‐polarization intensities is accompanied by low‐frequency instabilities detected on the scattered light intensities and plasma emission. It is found that the particle radius and particle number density during the agglomeration phase can be well described by the Brownian free molecule coagulation model. Application of this neutral particle coagulation model is justified by calculation of the particle charge whereby it is shown that particles of a few tens of nanometer can be considered as neutral under our experimental conditions. The measured particle dispersion can be well described by a Brownian free molecule coagulation model including a log‐normal particle size distribution.