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991.
Lucile Gust Alexis Toullec Charlotte Benoit René Farcy Stéphane Garcia Veronique Secq Jean-Yves Gaubert Delphine Trousse Bastien Orsini Christophe Doddoli Helene Moniz-Koum Pascal Alexandre Thomas Xavier Benoit D’journo 《PloS one》2015,10(8)
Background
Pre-therapeutic pathological diagnosis is a crucial step of the management of pulmonary nodules suspected of being non small cell lung cancer (NSCLC), especially in the frame of currently implemented lung cancer screening programs in high-risk patients. Based on a human ex vivo model, we hypothesized that an embedded device measuring endogenous fluorescence would be able to distinguish pulmonary malignant lesions from the perilesional lung tissue.Methods
Consecutive patients who underwent surgical resection of pulmonary lesions were included in this prospective and observational study over an 8-month period. Measurements were performed back table on surgical specimens in the operative room, both on suspicious lesions and the perilesional healthy parenchyma. Endogenous fluorescence signal was characterized according to three criteria: maximal intensity (Imax), wavelength, and shape of the signal (missing, stable, instable, photobleaching).Results
Ninety-six patients with 111 suspicious lesions were included. Final pathological diagnoses were: primary lung cancers (n = 60), lung metastases of extra-thoracic malignancies (n = 27) and non-tumoral lesions (n = 24). Mean Imax was significantly higher in NSCLC targeted lesions when compared to the perilesional lung parenchyma (p<0,0001) or non-tumoral lesions (p<0,0001). Similarly, photobleaching was more frequently found in NSCLC than in perilesional lung (p<0,0001), or in non-tumoral lesions (p<0,001). Respective associated wavelengths were not statistically different between perilesional lung and either primary lung cancers or non-tumoral lesions. Considering lung metastases, both mean Imax and wavelength of the targeted lesions were not different from those of the perilesional lung tissue. In contrast, photobleaching was significantly more frequently observed in the targeted lesions than in the perilesional lung (p≤0,01).Conclusion
Our results demonstrate that endogenous fluorescence applied to the diagnosis of lung nodules allows distinguishing NSCLC from the surrounding healthy parenchyma and from non-tumoral lesions. Inconclusive results were found for lung metastases due to the heterogeneity of this population. 相似文献992.
993.
Carmen Amador Jennifer Huffman Holly Trochet Archie Campbell David Porteous Generation Scotland James F Wilson Nick Hastie Veronique Vitart Caroline Hayward Pau Navarro Chris S Haley 《BMC genomics》2015,16(1)
Background
The Generation Scotland Scottish Family Health Study (GS:SFHS) includes 23,960 participants from across Scotland with records for many health-related traits and environmental covariates. Genotypes at ~700 K SNPs are currently available for 10,000 participants. The cohort was designed as a resource for genetic and health related research and the study of complex traits. In this study we developed a suite of analyses to disentangle the genomic differentiation within GS:SFHS individuals to describe and optimise the sample and methods for future analyses.Results
We combined the genotypic information of GS:SFHS with 1092 individuals from the 1000 Genomes project and estimated their genomic relationships. Then, we performed Principal Component Analyses of the resulting relationships to investigate the genomic origin of different groups. We characterised two groups of individuals: those with a few sparse rare markers in the genome, and those with several large rare haplotypes which might represent relatively recent exogenous ancestors. We identified some individuals with likely Italian ancestry and a group with some potential African/Asian ancestry. An analysis of homozygosity in the GS:SFHS sample revealed a very similar pattern to other European populations. We also identified an individual carrying a chromosome 1 uniparental disomy. We found evidence of local geographic stratification within the population having impact on the genomic structure.Conclusions
These findings illuminate the history of the Scottish population and have implications for further analyses such as the study of the contributions of common and rare variants to trait heritabilities and the evaluation of genomic and phenotypic prediction of disease.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1605-2) contains supplementary material, which is available to authorized users. 相似文献994.
Mass spectrometry-based clinical proteomics approaches were introduced into the biomedical field more than two decades ago. Despite recent developments both in the field of mass spectrometry and bioinformatics, the gap between proteomics results and their translation into clinical practice still needs to be closed, as implementation of proteomics results in the clinic appears to be scarce. An extra focus on the importance of the experimental design is therefore of crucial importance. 相似文献
995.
Verschaeve L Anthonissen R Grudniewska M Wudarski J Gevaert L Maes A 《Bioelectromagnetics》2011,32(7):580-584
We performed a genotoxicity investigation of extremely low-frequency (ELF) magnetic fields (MFs, 50 Hz, 100 and 500 μT, 1 and 2 h exposure) alone and in combination with known chemical mutagens using the VITOTOX test. This test is a very sensitive reporter assay of Salmonella typhimurium bacteria based on the SOS response. Our study showed that ELF-MFs do not induce SOS-based mutagenicity in S. typhimurium bacteria and do not show any synergetic effect when combined with chemical mutagens. 相似文献
996.
Sand M de Berardinis V Mingote A Santos H Göttig S Müller V Averhoff B 《Archives of microbiology》2011,193(10):723-730
Members of the genus Acinetobacter are well known for their metabolic versatility that allows them to adapt to different ecological niches. Here, we have addressed
how the model strain Acinetobacter baylyi copes with different salinities and low water activities. A. baylyi tolerates up to 900 mM sodium salts and even higher concentrations of potassium chloride. Growth at high salinities was better
in complex than in mineral medium and addition of glycine betaine stimulated growth at high salinities in mineral medium.
Cells grown at high salinities took up glycine betaine from the medium. Uptake of glycine betaine was energy dependent and
dependent on a salinity gradient across the membrane. Inspection of the genome sequence revealed two potential candidates
for glycine betaine transport, both encoding potential secondary transporters, one of the major facilitator superfamily (MFS)
class (ACIAD2280) and one of the betaine/choline/carnitine transporter (BCCT) family (ACIAD3460). The latter is essential
for glycine betaine transport in A. baylyi. The broad distribution of ACIAD3460 homologues indicates the essential role of secondary transporters in the adaptation of
Acinetobacter species to osmotic stress. 相似文献
997.
998.
Nearly twenty years of experimental immunotherapy for malignant glioma yielded important insights in the mechanisms governing
glioma immunology. Still considered promising, it is clear that immunotherapy does not on its own represent the magic bullet
in glioma therapy. In this review, we summarize the major immunotherapeutic achievements in the mouse GL261 glioma model,
which has emerged as the gold standard syngeneic model for experimental glioma therapy. Gene therapy, monoclonal antibody
treatment, cytokine therapy, cell transfer strategies and dendritic cell therapy were hereby considered. Apart from the considerable
progress made in understanding glioma immunology in this model, we also addressed its most pertinent issues and shortcomings.
Despite these, the GL261 model will remain indispensable in glioma research since it is a fast, highly reproducible and easy-to-establish
model system. 相似文献
999.
Ouakad M Vanaerschot M Rijal S Sundar S Speybroeck N Kestens L Boel L De Doncker S Maes I Decuypere S Dujardin JC 《Parasitology》2011,138(11):1392-1399
Mathematical models predict that the future of epidemics of drug-resistant pathogens depends in part on the competitive fitness of drug-resistant strains. Considering metacyclogenesis (differentiation process essential for infectivity) as a major contributor to the fitness of Leishmania donovani, we tested its relationship with pentavalent antimony (SbV) resistance in clinical lines. Different methods for the assessment of metacyclogenesis were cross-validated: gene expression profiling (META1 and SHERP), morphometry (microscopy and FACS), in vitro infectivity to macrophages and resistance to complement lysis. This was done on a model constituted by 2 pairs of reference strains cloned from a SbV-resistant and -sensitive isolate. We selected the most adequate parameter and extended the analysis of metacyclogenesis diversity to a sample of 20 clinical lines with different in vitro susceptibility to the drug. The capacity of metacyclogenesis, as measured by the complement lysis test, was shown to be significantly higher in SbV-resistant clinical lines of L. donovani than in SbV-sensitive lines. Together with other lines of evidence, it is concluded that L. donovani constitutes a unique example and model of drug-resistant pathogens with traits of increased fitness. These findings raise a fundamental question about the potential risks of selecting more virulent pathogens through massive chemotherapeutic interventions. 相似文献
1000.
Veronique C. A. Vos Jasper van Ruijven Matty P. Berg Edwin T. H. M. Peeters Frank Berendse 《Oikos》2011,120(7):1092-1098
The importance of leaf litter diversity for decomposition, an important process in terrestrial ecosystems, is much debated. Previous leaf litter‐mixing studies have shown that non‐additive leaf litter diversity effects can occur, but it is not clear why they occurred in only half of the studies and which underlying mechanisms can explain these conflicting results. We hypothesized that incorporating the role of macro‐detritivores could be important. Although often ignored, macro‐detritivores are known to strongly influence decomposition. To better understand the importance of macro‐detritivores for leaf litter mixing effects during decomposition, four common leaf litter species were added separately and in two and four species combinations to monocultures of three different macro‐detritivores and a control without fauna. Our results clearly show that leaf litter‐mixing effects occurred only in the presence of two macro‐detritivores (earthworms and woodlice). Application of the additive partitioning method revealed that in the specific combination of woodlice and the presence of a slow‐decomposing leaf litter species in the mixture, leaf litter mixing effects were strongly driven by a selection effect. This was caused by food preference of the isopod: the animals avoided the slow decomposing species when given the choice. However, most leaf litter mixing effects were caused by complementarity effects. The potential mechanisms underlying the complementarity effects are discussed. Our results clearly show that that both leaf litter and macro‐detritivore identity can affect litter diversity. This may help to explain the conflicting results obtained in previous experiments. 相似文献