101 research outputs found
Improved survival following surgery and radiation therapy for olfactory neuroblastoma: analysis of the SEER database
<p>Abstract</p> <p>Background</p> <p>Olfactory Neuroblastoma is a rare malignant tumor of the olfactory tract. Reports in the literature comparing treatment modalities for this tumor are limited.</p> <p>Methods</p> <p>The SEER database (1973-2006) was queried by diagnosis code to identify patients with Olfactory Neuroblastoma. Kaplan-Meier was used to estimate survival distributions based on treatment modality. Differences in survival distributions were determined by the log-rank test. A Cox multiple regression analysis was then performed using treatment, race, SEER historic stage, sex, age at diagnosis, year at diagnosis and SEER geographic registry.</p> <p>Results</p> <p>A total of 511 Olfactory Neuroblastoma cases were reported. Five year overall survival, stratified by treatment modality was: 73% for surgery with radiotherapy, 68% for surgery only, 35% for radiotherapy only, and 26% for neither surgery nor radiotherapy. There was a significant difference in overall survival between the four treatment groups (p < 0.01). At ten years, overall survival stratified by treatment modality and stage, there was no significant improvement in survival with the addition of radiation to surgery.</p> <p>Conclusions</p> <p>Best survival results were obtained for surgery with radiotherapy.</p
Limited variability in the phytoplankton Emiliania huxleyi since the pre-industrial era in the Subantarctic Southern Ocean
The Southern Ocean is warming faster than the average global ocean and is particularly vulnerable to
ocean acidification due to its low temperatures and moderate alkalinity. Coccolithophores are the most
productive calcifying phytoplankton and an important component of Southern Ocean ecosystems.
Laboratory observations on the most abundant coccolithophore, Emiliania huxleyi, suggest that this
species is susceptible to variations in seawater carbonate chemistry, with consequent impacts in the
carbon cycle. Whether anthropogenic environmental change during the industrial era has modified
coccolithophore populations in the Southern Ocean, however, remains uncertain. This study analysed the
coccolithophore assemblage composition and morphometric parameters of E. huxleyi coccoliths of a suite
of Holocene-aged sediment samples from south of Tasmania. The analysis suggests that dissolution
diminished the mass and length of E. huxleyi coccoliths in the sediments, but the thickness of the
coccoliths was decoupled from dissolution allowing direct comparison of samples with different degree
of preservation. The latitudinal distribution pattern of coccolith thickness mirrors the latitudinal
environmental gradient in the surface layer, highlighting the importance of the geographic distribution of
E. huxleyi morphotypes on the control of coccolith morphometrics. Additionally, comparison of the E.
huxleyi coccolith assemblages in the sediments with those of annual subantarctic sediment trap records
found that modern E. huxleyi coccoliths are
2% thinner than those from the pre-industrial era. The subtle
variation in coccolith thickness contrasts sharply with earlier work that documented a pronounced
reduction in shell calcification and consequent shell-weight decrease of
30-35% on the planktonic
foraminifera Globigerina bulloides induced by ocean acidification. Results of this study underscore the
varying sensitivity of different marine calcifying plankton groups to ongoing environmental change.FCT: UIDB/04326/2020;info:eu-repo/semantics/publishedVersio
Análisis de la morfometría ósea en ratas sometidas a diferentes situaciones de hipoxia
El hueso es uno de los tejidos metabólicamente más activos, metabolismo que requiere de un aporte suficiente de oxígeno. En este sentido, se han publicado resultados contradictorios de cómo la hipoxia podría modificar el remodelado óseo y con ello la estructura del hueso. El objetivo del estudio fue valorar el efecto de la hipoxia sobre la morfometría ósea y la densidad mineral ósea medidas por tomografía axil computarizada de alta resolución (HR-pQTc ). Se analizaron 61 ratas wistar a las que se les sometió a diferentes condiciones experimentales: ratas control (sometidas a condiciones de normoxia), ratas sometidas a hipoxia crónica constante y ratas sometidas a hipoxia crónica intermitente. Los animales se sacrificaron por una sobredosis cardiaca de fenobarbital. A continuación, se procedió a la extracción de los huesos, fémur y tibia. Posteriormente se fijaron en etanol al 70% para su posterior análisis. Se utilizó un micro-TAC modelo escáner SKYSCAN 1172 de la marca BRUKER y un software de captación de datos skyscan1172 µCT. La reconstrucción de las imágenes se realizó mediante un software Nrecon utilizándose posterio mente el software de análisis de imagen "CTAN". Se utilizó el SPSS v22 para el análisis estadístico. Nuestros resultados mostraron que las ratas sometidas a condiciones de hipoxia tenían una menor densidad mineral de tejido (TMD) en fémur cortical y un menor grosor trabecular de la tibia. Por otra parte, analizando las ratas sometidas a hipoxia crónica permanente en referencia a las ratas control, se observó que la hipoxia se asoció con un menor espesor cortical de la tibia, menor densidad mineral ósea (BMD) en fémur trabecular y con menor volumen óseo porcentual (BV/TV) del fémur trabecular. Diferenciando por sexos, las ratas hembras sometidas a hipoxia crónica permanente presentaron un menor espesor de la tibia cortical, menor grosor de las trabéculas de la tibia y el fémur y menores valores de BMD en las trabéculas de la tibia y el fémur. Las ratas macho sometidas a hipoxia crónica permanente, tenían un menor número de trabéculas en la tibia. También se observó como las ratas sometidas a hipoxia permanente intermitente, tenían un menor TMD que las ratas control. Nuestros resultados mostraron que en diferentes condiciones de hipoxia se observó un deterioro de la morfometría ósea, probablemente debido a que se produce una alteración del remodelado óseo promovido por la hipoxia tisular
Morphological and molecular analysis of natural hybrids between the diploid Centaurea aspera L. and the tetraploid C. seridis L. (Compositae)
[EN] Polyploidy and hybridisation are the basis of the evolution of Centaurea (Compositae). At the El Saler dune field (eastern Spain), the diploid Centaurea aspera ssp. stenophylla and the tetraploid C. seridis ssp. maritima form a polyploid complex in which C. x subdecurrens individuals occur. This polyploid complex was analysed morphologically and genetically, using random amplified polymorphic DNA (RAPD) and tubulin-based polymorphism (TBP) markers. Flow cytometry showed that the hybrids are triploid, which is a rare finding in Centaurea. Morphologically, in contrast to leaf characters, flowering characters clearly discriminated the three taxa. The genetic analyses confirm that C. x subdecurrens is a result of the hybridisation between Centaurea aspera ssp. stenophylla and C. seridis ssp. maritima, and suggest that backcrossing events and gene flow are very rare or absent. Although the hybrids likely represent true F1 offspring, they displayed some genetic diversity that is probably due to the combination of alleles. Genetic diversity was higher in diploid than in tetraploid individuals. This fact, and the high degree of sterility of the triploid hybrids, may reflect a cytotype minority exclusion effect. This may cause spatial segregation, which effectively takes place in the study area. Dune disturbance may lead to an overlapping of the parents' distribution areas, facilitating hybridisation.This work is posthumously dedicated to Antonio Samo Lumbreras, to whom we are very grateful for all his help. This study was sponsored by the Valencian Government (Research Project GVPRE/2008/130) and the Universitat Politecnica de Valencia (Research Project Ref. 3241).Ferriol Molina, M.; Garmendia, A.; Ruiz, J.; Merle Farinós, HB.; Boira Tortajada, H. (2012). Morphological and molecular analysis of natural hybrids between the diploid Centaurea aspera L. and the tetraploid C. seridis L. (Compositae). Plant Biosystems. 146(1):86-100. https://doi.org/10.1080/11263504.2012.727878S86100146
TP53 regulates human AlkB homologue 2 expression in glioma resistance to Photofrin-mediated photodynamic therapy
2010-2011 > Academic research: refereed > Publication in refereed journa
Photodynamic therapy augments the efficacy of oncolytic vaccinia virus against primary and metastatic tumours in mice
in mic
Quantitative comparison of taxa and taxon concepts in the diatom genus Fragilariopsis: a case study on using slide scanning, multi‐expert image annotation and image analysis in taxonomy
Semi‐automated methods for microscopic image acquisition, image analysis and taxonomic identification have repeatedly received attention in diatom analysis. Less well studied is the question whether and how such methods might prove useful for clarifying the delimitation of species that are difficult to separate for human taxonomists. To try to answer this question, three very similar Fragilariopsis species endemic to the Southern Ocean were targeted in this study: F. obliquecostata, F. ritscheri, and F. sublinearis. A set of 501 extended focus depth specimen images were obtained using a standardized, semi‐automated microscopic procedure. Twelve diatomists independently identified these specimen images in order to reconcile taxonomic opinions and agree upon a taxonomic gold standard. Using image analyses, we then extracted morphometric features representing taxonomic characters of the target taxa. The discriminating ability of individual morphometric features was tested visually and statistically, and multivariate classification experiments were performed to test the agreement of the quantitatively‐defined taxa assignments with expert consensus opinion. Beyond an updated differential diagnosis of the studied taxa, our study also shows that automated imaging and image analysis procedures for diatoms are coming close to reaching a broad applicability for routine use
A formal classification of the Lygeum spartum vegetation of the Mediterranean Region
Aims We examined local and regional contribution on the grasslands dominated by Lygeum spartum from Southern Europe and North Africa to produce a formalised classification of this vegetation and to identify main factors driving its plant species composition. Location Mediterranean Basin and Iberian Peninsula. Methods We used a dataset of 728 relevés, which were resampled to reduce unbalanced sampling effort, resulting in a dataset of 568 relevés and 846 taxa. We classified the plots by TWINSPAN, interpreted the resulting pools, and used them to develop formal definitions of phytosociological alliances characterised by L. spartum vegetation. The definitions were included in an expert system to assist automatic vegetation classification. We related the alliances to climatic factors and described their biogeographical features and ecological preferences. The floristic relationships between these alliances were analysed and visualised using distance‐based redundancy analysis. Results We defined eleven alliances of L. spartum vegetation, including the newly described Launaeo laniferae‐Lygeion sparti from SW Morocco and the Noaeo mucronatae‐Lygeion sparti from the Algerian highlands and NE Morocco. Biogeographical, climatic, and edaphic factors were revealed as putatively driving the differentiation between the alliances. The vegetation of clayey slopes and inland salt basins displayed higher variability in comparison with those of coastal salt marshes. Main conclusions The most comprehensive formal classification, accompanied by an expert system, of the L. spartum vegetation was formulated. The expert system, containing the formal definitions of the phytosociological alliances, will assist in identification of syntaxonomic position of new datasets
Resupply of mesopelagic dissolved iron controlled by particulate iron composition
The dissolved iron supply controls half of the oceans’ primary productivity. Resupply by the remineralization of sinking particles, and subsequent vertical mixing, largely sustains this productivity. However, our understanding of the drivers of dissolved iron resupply, and their influence on its vertical distribution across the oceans, is still limited due to sparse observations. There is a lack of empirical evidence as to what controls the subsurface iron remineralization due to difficulties in studying mesopelagic biogeochemistry. Here we present estimates of particulate transformations to dissolved iron, concurrent oxygen consumption and iron-binding ligand replenishment based on in situ mesopelagic experiments. Dissolved iron regeneration efficiencies (that is, replenishment over oxygen consumption) were 10- to 100-fold higher in low-dust subantarctic waters relative to higher-dust Mediterranean sites. Regeneration efficiencies are heavily influenced by particle composition. Their make-up dictates ligand release, controls scavenging, modulates ballasting and may lead to the differential remineralization of biogenic versus lithogenic iron. At high-dust sites, these processes together increase the iron remineralization length scale. Modelling reveals that in oceanic regions near deserts, enhanced lithogenic fluxes deepen the ferricline, which alter the vertical patterns of dissolved iron replenishment, and set its redistribution at the global scale. Such wide-ranging regeneration efficiencies drive different vertical patterns in dissolved iron replenishment across oceanic provinces
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