900 resultados para Fluorescence in situ hybridisation (fish)


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Muchas respuestas a preguntas básicas sobre relaciones evolutivas, ubicación sistemática y evolución de caracteres morfológicos y ecológicos pueden ser obtenidas a través de las reconstrucciones filogenéticas. Sobre este contexto se pretende encarar en este proyecto estudios de filogenia molecular, revisiones sistemáticas, biología reproductiva y citogenética en Solanáceas americanas. Se intentará resolver la delimitación específica de Solanum sect. Solanum y Geminata, y Capsicum, y establecer relaciones filogenéticas en estos grupos. Se harán revisiones analizándose caracteres vegetativos y reproductivos críticos para evaluar su variabilidad y definir su valor taxonómico; para los estudios moleculares se utilizarán los marcadores ndhF, trnT-L, trnL-F y waxy. En base a los resultados se propondrán agrupamientos y relaciones de parentesco. Además, se hará un estudio cariosistemático para caracterizar y circunscribir especies en Solanum y miembros de la tribu Physaleae, y hasta variedades y/o cultivares en Capsicum, mediante técnicas clásicas y de bandeos de fluorescencia y AgNOR e hibridación in situ fluorescente (FISH). A nivel reproductivo, se estudiará la ecofisiología en las estructuras masculinas y su incidencia en la fructificación en Capscium baccatum. El desarrollo de esta temática comprende experiencias in vivo (a campo y en laboratorio) así como estudios histológicos y químicos.Se espera avanzar en la resolución de algunos problemas: 1) la complicada delimitación de especies de los taxones en estudio; 2) las relaciones filogenéticas en algunos de ellos; 3) la falta de conocimiento de la organización genómica; 4) el origen de las especies cultivadas de Capsicum. En cuanto a la biología reproductiva, para C. baccatum se pretende avanzar en el conocimiento de variables de relevancia en la reproducción, en especial los efectos del ambiente.

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Background: Several studies have demonstrated clinical benefits of fish consumption for the cardiovascular system. These effects are attributed to the increased amounts of polyunsaturated fatty acids in these foods. However, the concentrations of fatty acids may vary according to region. Objective: The goal of this study was to determine the amount of,cholesterol and fatty acids in 10 Brazilian fishes and in a non-native farmed salmon usually consumed in Brazil. Methods: The concentrations of cholesterol and fatty acids, especially omega-3, were determined in grilled fishes. Each fish sample was divided in 3 sub-samples (chops) and each one was extracted from the fish to minimize possible differences in muscle and fat contents. Results: The largest cholesterol amount was found in white grouper (107.6 mg/100 g of fish) and the smallest in badejo (70 mg/100 g). Omega-3 amount varied from 0.01 g/100 g in badejo to 0.900 g/100 g in weakfish. Saturated fat varied from 0.687 g/100 g in seabass to 4.530 g/100 g in filhote. The salmon had the greatest concentration of polyunsaturated fats (3.29 g/100 g) and the highest content of monounsaturated was found in pescadinha (5.98 g/100 g). Whiting and boyfriend had the best omega-6/omega 3 ratios respectively 2.22 and 1.19, however these species showed very little amounts of omega-3. Conclusion: All studied Brazilian fishes and imported salmon have low amounts of saturated fat and most of them also have low amounts of omega-3.

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Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2009

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Magdeburg, Univ., Fak. für Verfahrens- und Systemtechnik, Diss., 2010

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Die Mesostruktur von Werkstoffen wie Faserverbundwerkstoffen und Schaumstoffen beeinflusst deren mechanisches Verhalten wesentlich. Die inneren Strukturen des Werkstoffes müssen in die Analyse des Verformungs- und Versagensverhaltens einbezogen werden. Die Röntgenanalyse, insbesondere die Röntgen-Computertomographie (Röntgen-CT) ermöglicht eine zerstörungsfreie 3-dimensionale (3-d) Visualisierungund Charakterisierung innerer Strukturen. Für die Untersuchung des Einflusses der Mesostruktur eines Polymethacrymlid-Hartschaumstoffes auf das mechanische Verhalten speziell unter zugbelastung sollte eine speziell vom Fraunhofer-Institut für Werkstoffmechanik in Halle entwickelte In-situ-Verformungseinrichtung erprobt werden. Die Anlage wurde speziell für den Zugversuch optimiert. Es folgten mechanische Experimente, die mit den 3d-Bilddaten der Zellstruktur des Schaumstoffes korrelieren. Die ermittelten Bilddaten werden mit Hilfe einer Bildanalysesoftware ausgewertet und Rückschlüsse auf Verformungs- und Versagensverhalten grtroffen.

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Raman spectroscopy has been applied to characterize fiber dyes and determine the discriminating ability of the method. Black, blue, and red acrylic, cotton, and wool samples were analyzed. Four excitation sources were used to obtain complementary responses in the case of fluorescent samples. Fibers that did not provide informative spectra using a given laser were usually detected using another wavelength. For any colored acrylic, the 633-nm laser did not provide Raman information. The 514-nm laser provided the highest discrimination for blue and black cotton, but half of the blue cottons produced noninformative spectra. The 830-nm laser exhibited the highest discrimination for red cotton. Both visible lasers provided the highest discrimination for black and blue wool, and NIR lasers produced remarkable separation for red and black wool. This study shows that the discriminating ability of Raman spectroscopy depends on the fiber type, color, and the laser wavelength.

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The Mont Collon mafic complex is one of the best preserved examples of the Early Permian magmatism in the Central Alps, related to the intra-continental collapse of the Variscan belt. It mostly consists (> 95 vol.%) of ol+hy-nonnative plagioclase-wehrlites, olivine- and cpx-gabbros with cumulitic structures, crosscut by acid dikes. Pegmatitic gabbros, troctolites and anorthosites outcrop locally. A well-preserved cumulative, sequence is exposed in the Dents de Bertol area (center of intrusion). PT-calculations indicate that this layered magma chamber emplaced at mid-crustal levels at about 0.5 GPa and 1100 degrees C. The Mont Collon cumulitic rocks record little magmatic differentiation, as illustrated by the restricted range of clinopyroxene mg-number (Mg#(cpx)=83-89). Whole-rock incompatible trace-element contents (e.g. Nb, Zr, Ba) vary largely and without correlation with major-element composition. These features are characteristic of an in-situ crystallization process with variable amounts of interstitial liquid L trapped between the cumulus mineral phases. LA-ICPMS measurements show that trace-element distribution in the latter is homogeneous, pointing to subsolidus re-equilibration between crystals and interstitial melts. A quantitative modeling based on Langmuir's in-situ crystallization equation successfully duplicated the REE concentrations in cumulitic minerals of all rock facies of the intrusion. The calculated amounts of interstitial liquid L vary between 0 and 35% for degrees of differentiation F of 0 to 20%, relative to the least evolved facies of the intrusion. L values are well correlated with the modal proportions of interstitial amphibole and whole-rock incompatible trace-element concentrations (e.g. Zr, Nb) of the tested samples. However, the in-situ crystallization model reaches its limitations with rock containing high modal content of REE-bearing minerals (i.e. zircon), such as pegmatitic gabbros. Dikes of anorthositic composition, locally crosscutting the layered lithologies, evidence that the Mont Collon rocks evolved in open system with mixing of intercumulus liquids of different origins and possibly contrasting compositions. The proposed model is not able to resolve these complex open systems, but migrating liquids could be partly responsible for the observed dispersion of points in some correlation diagrams. Absence of significant differentiation with recurrent lithologies in the cumulitic pile of Dents de Bertol points to an efficiently convective magma chamber, with possible periodic replenishment, (c) 2005 Elsevier B.V. All rights reserved.

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Detection of papillomavirus DNA in sity hybridization technique was perfomed in 29 symptomatic patients (6 males and 23 females) during the period of 1989-1991 at the Clinic for Sexually Transmitted Diseases, Universidade Federal Fluminense, State of rio de Janeiro. All the male patients had condyloma acuminata. Only HPV 6/11 were found in these lesions. Clinical features inthe female patients included vulvar condyloma acuminata, bowenoid populosis, flat cervical condyloma, cervical condyloma acuminatum and cervical intraepithelialneoplasia grade II (CIN II). We also found cases of condyloma acuminata associated to vulvar intraepithelial neoplasia grade III (VIN III), as well as to vaginal invasive carcinoma. HPV 6/11 and 16/18 were found in vulvar condyloma acuminata. Mixed infection by 6/11-16/18 HPV were also seen in these lesions as well as in the patient who had cervical condyloma acuminatum. HPV 16/18 were found in the condyloma acuminatum plus VIN III and in the CIN II lesions. We have found HPV31/33/51 in the specimen of condyloma acuminatum plus invasive carcinoma. In order to investigate the ultrastructural aspects of HPV infection in genital tissue, the biopsies of three female patients were observed under electron microscope.Mature virus particles were found in the cells of a condyloma acuminatum as wellas in the condyloma acuminatum plus invasive carcinoma case. In another sample, chromosome breakages were found in the nuclei of the infected cells although no viral particles were observed.

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Despite the advantage of avoiding the costs of sexual reproduction, asexual vertebrates are very rare and often considered evolutionarily disadvantaged when compared to sexual species. Asexual species, however, may have advantages when colonizing (new) habitats or competing with sexual counterparts. They are also evolutionary older than expected, leaving the question whether asexual vertebrates are not only rare because of their 'inferior' mode of reproduction but also because of other reasons. A paradigmatic model system is the unisexual Amazon molly, Poecilia formosa, that arose by hybridization of the Atlantic molly, Poecilia mexicana, as the maternal ancestor, and the sailfin molly, Poecilia latipinna, as the paternal ancestor. Our extensive crossing experiments failed to resynthesize asexually reproducing (gynogenetic) hybrids confirming results of previous studies. However, by producing diploid eggs, female F(1) -hybrids showed apparent preadaptation to gynogenesis. In a range-wide analysis of mitochondrial sequences, we examined the origin of P. formosa. Our analyses point to very few or even a single origin(s) of its lineage, which is estimated to be approximately 120,000 years old. A monophyletic origin was supported from nuclear microsatellite data. Furthermore, a considerable degree of genetic variation, apparent by high levels of clonal microsatellite diversity, was found. Our molecular phylogenetic evidence and the failure to resynthesize the gynogenetic P. formosa together with the old age of the species indicate that some unisexual vertebrates might be rare not because they suffer the long-term consequences of clonal reproduction but because they are only very rarely formed as a result of complex genetic preconditions necessary to produce viable and fertile clonal genomes and phenotypes ('rare formation hypothesis').

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Formalin-fixed paraffin embedded lung and liver tissue from 23 cases of non immune hydrops fetalis and five control cases, in which hydrops were due to syphilis (3) and genetic causes (2), were examined for the presence of human parvovirus B19 by DNA hybridisation. Using in situ hybridisation with a biotynilated probe one positive case was detected. Using 32P-labelled probes in a dot blot assay format, five further positives were obtained. These were all confirmed as positive by a nested polymerase chain reaction assay. Electron microscopy revealed virus in all these five positive cases. The six B19 DNA positive cases of hydrops fetalis were from 1974, 1980, 1982, 1987 and 1988, four of which occurred during the second half of the year, confirming the seasonality of the disease.

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The cell surface receptor Fas (Apo-1/CD95) and its ligand (FasL) are mediators of apoptosis that have been shown to be implicated in activation-induced death of mature T cells and in killing mediated by cytolytic T cells. The role of the Fas pathway in apoptosis associated with thymic selection events is, however, controversial. Although Fas and FasL are known to be expressed in the thymus, the nature and in vivo localization of FasL-expressing cells have not been determined. Using recently developed anti-FasL Abs in combination with in situ hybridization on tissue sections, we show in this work that FasL-expressing cells are present in the thymus, particularly within the medulla. FasL mRNA was detected readily in thymic stromal cell extracts, but not in isolated thymocytes. Moreover, immunohistochemical analysis of serial tissue sections stained with Abs against FasL in conjunction with epithelial and dendritic cell markers indicated that both thymic epithelial and dendritic cells express FasL in situ. The coexistence of FasL-expressing stromal cells and Fas-expressing thymocytes may have important implications for the role of the Fas pathway in apoptosis associated with thymic selection events.

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We investigated the use of in situ implant formation that incorporates superparamagnetic iron oxide nanoparticles (SPIONs) as a form of minimally invasive treatment of cancer lesions by magnetically induced local hyperthermia. We developed injectable formulations that form gels entrapping magnetic particles into a tumor. We used SPIONs embedded in silica microparticles to favor syringeability and incorporated the highest proportion possible to allow large heating capacities. Hydrogel, single-solvent organogel and cosolvent (low-toxicity hydrophilic solvent) organogel formulations were injected into human cancer tumors xenografted in mice. The thermoreversible hydrogels (poloxamer, chitosan), which accommodated 20% w/v of the magnetic microparticles, proved to be inadequate. Alginate hydrogels, however, incorporated 10% w/v of the magnetic microparticles, and the external gelation led to strong implants localizing to the tumor periphery, whereas internal gelation failed in situ. The organogel formulations, which consisted of precipitating polymers dissolved in single organic solvents, displayed various microstructures. A 8% poly(ethylene-vinyl alcohol) in DMSO containing 40% w/v of magnetic microparticles formed the most suitable implants in terms of tumor casting and heat delivery. Importantly, it is of great clinical interest to develop cosolvent formulations with up to 20% w/v of magnetic microparticles that show reduced toxicity and centered tumor implantation.

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OBJECTIVES: The purpose of this study was to assess short- and mid-term results of in-situ revascularisation (ISR) using silver-coated Dacron prostheses and bowel repair for management of secondary aorto-enteric fistulae (SAEF). DESIGN: Single-centre retrospective chart review. MATERIAL AND METHODS: This study includes all the patients treated by ISR using silver-coated Dacron for SAEF between 2006 and 2010. Primary end points were mortality and survival rates. Secondary end points were reinfection-free survival and secondary patency rates. RESULTS: Eighteen male patients with SAEF with a median age of 64 years were operated by ISR using silver-coated Dacron during the study period without operative death. The 30-day mortality was 22% and the in-hospital mortality rate was 39%. Indeed, during hospitalisation, a duodenal leak was observed in four patients including three who died. Four others patients died due to multi-system organ failure. Median follow-up was 16 months (range 1-66). The survival rate at 12 months was 55%. One duodenal leak was observed leading to death. The reinfection-free survival and the secondary patency rates at 12 months were 60% and 89%, respectively. CONCLUSION: In-situ revascularisation with silver-coated Dacron provides acceptable results in terms of mortality. This treatment may be useful for simple vascular reconstruction and allow greater attention to bowel repair that is a determinant in short- and mid-term survival.

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Ductal carcinoma in situ (DCIS), accounting for 15-25% of all breast cancers, is frequently diagnosed by mammographic examination. This heterogeneous disease requires a rigorous local treatment based, in about two-third of cases, on conservative surgery and radiotherapy. DCIS are currently classified on the basis of nuclear grade. Most lesions, and especially high nuclear grade DCIS, are limited to one quadrant. Micropapillary DCIS are likely to be of larger size/extent and thus a conservative approach is often difficult. A careful pathological examination of an oriented excisional biopsy is a pre-requisite for optimal therapy.