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161.
Andoni Ramirez-Garcia Beatriz Arteta Ana Abad-Diaz-de-Cerio Aize Pellon Aitziber Antoran Joana Marquez Aitor Rementeria Fernando L. Hernando 《PloS one》2013,8(1)
The dimorphic fungus Candida albicans is able to trigger a cytokine-mediated pro-inflammatory response that increases tumor cell adhesion to hepatic endothelium and metastasis. To check the intraspecific differences in this effect, we used an in vitro murine model of hepatic response against C. albicans, which made clear that tumor cells adhered more to endothelium incubated with blastoconidia, both live and killed, than germ tubes. This finding was related to the higher carbohydrate/protein ratio found in blastoconidia. In fact, destruction of mannose ligand residues on the cell surface by metaperiodate treatment significantly reduced tumor cell adhesion induced. Moreover, we also noticed that the effect of clinical strains was greater than that of the reference one. This finding could not be explained by the carbohydrate/protein data, but to explain these differences between strains, we analyzed the expression level of ten genes (ADH1, APE3, IDH2, ENO1, FBA1, ILV5, PDI1, PGK1, QCR2 and TUF1) that code for the proteins identified previously in a mannoprotein-enriched pro-metastatic fraction of C. albicans. The results corroborated that their expression was higher in clinical strains than the reference one. To confirm the importance of the mannoprotein fraction, we also demonstrate that blocking the mannose receptor decreases the effect of C. albicans and its mannoproteins, inhibiting IL-18 synthesis and tumor cell adhesion increase by around 60%. These findings could be the first step towards a new treatment for solid organ cancers based on the role of the mannose receptor in C. albicans-induced tumor progression and metastasis. 相似文献
162.
Sarah L. Eggers Aleksandra M. Lewandowska Joana Barcelos e Ramos Sonia Blanco‐Ameijeiras Francesca Gallo Birte Matthiessen 《Global Change Biology》2014,20(3):713-723
Ecosystem functioning is simultaneously affected by changes in community composition and environmental change such as increasing atmospheric carbon dioxide (CO2) and subsequent ocean acidification. However, it largely remains uncertain how the effects of these factors compare to each other. Addressing this question, we experimentally tested the hypothesis that initial community composition and elevated CO2 are equally important to the regulation of phytoplankton biomass. We full‐factorially exposed three compositionally different marine phytoplankton communities to two different CO2 levels and examined the effects and relative importance (ω2) of the two factors and their interaction on phytoplankton biomass at bloom peak. The results showed that initial community composition had a significantly greater impact than elevated CO2 on phytoplankton biomass, which varied largely among communities. We suggest that the different initial ratios between cyanobacteria, diatoms, and dinoflagellates might be the key for the varying competitive and thus functional outcome among communities. Furthermore, the results showed that depending on initial community composition elevated CO2 selected for larger sized diatoms, which led to increased total phytoplankton biomass. This study highlights the relevance of initial community composition, which strongly drives the functional outcome, when assessing impacts of climate change on ecosystem functioning. In particular, the increase in phytoplankton biomass driven by the gain of larger sized diatoms in response to elevated CO2 potentially has strong implications for nutrient cycling and carbon export in future oceans. 相似文献
163.
We hypothesized that distribution and microhabitat use by imperilled chub Squalius torgalensis in the Torgal stream, Portugal, during low flows, were related to spatial patchiness in physical resources and shifts in ontogenetic preferences. We mapped fish abundance and sampled microhabitat use and availability via snorkelling. We used the coefficient of dispersion in abundance, and spatial autocorrelation analyses to characterize chub distribution, and Hurdle models to relate chub presence and abundance to habitat characteristics. We showed that chub displayed an aggregated distribution, apparently in association with patchily distributed and autocorrelated physical resources, such as debris, roots and aquatic vegetation. Microhabitat use generally was unrelated to velocity, and ontogenetic differences in microhabitat use were not substantial. Nevertheless, sometimes small chub preferred low-velocity patches with coarse substrata, debris and roots, whereas large chub preferred deeper patches with roots and aquatic vegetation. Results suggest that, in low flow conditions, chub respond to resource patchiness by congregating in favourable microhabitats, and that maintenance of mosaics of patches with variable substrata, cover and depth may be important for the persistence of fish in Mediterranean streams. 相似文献
164.
Mara Ribeiro Almeida Joana D’Arc Castania Darin Lívia Cristina Hernandes M?nica Freiman de Souza Ramos Lusania Maria Greggi Antunes Osvaldo de Freitas 《Genetics and molecular biology》2012,35(3):664-672
Copaiba oil-resin, extracted from the trunk of Copaifera, and traditionally used in folk medicine in the treatment of various disorders, has been shown to be an effective antiinflamatory, antitumor, antitetanus, antiseptic and anti-blenorrhagea agent. As, there are few studies evaluating its genotoxicity, this aspect of the commercial oil-resin, and its volatile and resinous fractions, were evaluated in mice by comet assay and micronucleus (MN) test. A single dose of oil resin, volatile or resin fractions (500; 1,000 or 2,000 mg/kg b.w.) was administered by gavage. The chemical compositions of Copaiba oil resin and its fractions was analyzed by gas chromatography. According to comet assaying, treatment with either one did not increase DNA damage, and as to MN testing, there was no alteration in the incidence of micronucleated polychromatic erythrocytes. Chromatographic analysis of the oil-resin itself revealed sesquiterpenes, diterpenic carboxylic acid methyl esters and high levels of β-caryophyllene. Thus, it can be assumed that the oil resin and volatile and resinous fractions from the commercial product are not genotoxic or mutagenic. 相似文献
165.
Joana Pinheiro Darlene Rodrigues Pedro Fernandes Alexandre Pereira Lurdes Trigo 《Reports of Practical Oncology and Radiotherapy》2018,23(5):322-330
Introduction
The incidence of breast carcinoma (BC) has increased in the last years. Between 2 and 12% of patients diagnosed with BC will develop bilateral breast carcinoma (BBC). The treatment of these carcinomas is more aggressive than unilateral BC.Purpose
To perform a retrospective qualitative analysis of BBC patients whose treatment has included brachytherapy (BT) and to present a revised literature on this issue.Material and methods
The cases of BBC whose treatment included brachytherapy were revised. The literature on this issue was refreshed.Results
Five women, aged between 54 and 78 at the time of the diagnosis, submitted to conservative surgery followed by external radiotherapy (RT) with boost of BT or exclusive BT (APBI), in the IPO-P BT Service between 2003 and 2016.Discussion
The patients with BBC have slightly higher rates of local recurrences, mostly in the tumor bed, where there is a higher risk of local recurrence. Patients treated with BT had lower rates of recurrences than those treated with photons and electrons.Conclusions
BBC represents a complex challenge for doctors, because in some cases there is a tendency to use more aggressive treatments and, at the same time, it is not easy to achieve the timing for the correct treatment. 相似文献166.
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Mangrove rice farmers in Guinea-Bissau are facing climatic changes (i.e., seawater flooding and decreasing rainfall) that threaten their livelihood. In addition, cultural transformations (e.g., abandonment of bush initiations) have affected inter-generational knowledge exchange and elders’ control over youth. Our ethnographic research documents the construction of a dam in a village in southern Guinea-Bissau to protect rice farms from seawater flooding. In a struggle for increased access to land, the youth of the village formed an association to ensure the availability of labor and promote knowledge exchange. Inter-village expert knowledge of mangrove rice farming is disseminated through networks of reciprocity that exist alongside village, household, and age-based knowledge transmission. Farmers’ capacity to experiment with technological solutions and expand the connections in regional knowledge networks is crucial to ongoing adaptation. Multidimensional rural development strategies are of importance to respond to changing climatic and socio-cultural conditions. 相似文献