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61.
Dimitrios Damalas Christos D. Maravelias Giacomo C. Osio Francesc Maynou Mario Sbrana Paolo Sartor 《PloS one》2015,10(3)
We investigate long-term changes in the Mediterranean marine resources driving the trawl fisheries by analysing fishers’ perceptions (Traditional Ecological Knowledge, TEK) throughout the Mediterranean Sea during the last 80 years. To this end, we conducted an extended set of interviews with experienced fishers that enabled us to classify species (or taxa) as ‘decreasing’ or ‘increasing’ both in terms of abundance, as well as average size in the catch. The aspect that most clearly emerged in all the investigated areas over time was the notable increase of fishing capacity indicators, such as engine power and fishing depth range. Atlantic mackerel, poor cod, scorpionfishes, striped seabream, and John Dory demonstrated a decreasing trend in the fishers’ perceived abundance, while Mediterranean parrotfish, common pandora, cuttlefish, blue and red shrimp, and mullets gave indications of an increasing temporal trend. Although, as a rule, trawler captains did not report any cataclysmic changes (e.g. extinctions), when they were invited to estimate total catches, a clear decreasing pattern emerged; this being a notable finding taking into account the steep escalation of fishing efficiency during the past century. The overall deteriorating status of stocks in most Mediterranean regions calls for responsible management and design of rebuilding plans. This should include historical information accounting for past exploitation patterns that could help defining a baseline of fish abundance prior to heavy industrial fisheries exploitation. 相似文献
62.
Sofia Agelaki Antonia Kalykaki Harris Markomanolaki Maria A. Papadaki Galatea Kallergi Dora Hatzidaki Kostas Kalbakis Dimitrios Mavroudis Vassilis Georgoulias 《PloS one》2015,10(6)
Background
To evaluate the efficacy of lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, in therapy-resistant HER2-positive CTCs in metastatic breast cancer (MBC).Patients and Methods
Patients with MBC and HER2-positive CTCs despite disease stabilization or response to prior therapy, received lapatinib 1500 mg daily in monthly cycles, till disease progression or CTC increase. CTC monitoring was performed by immunofluorescent microscopy using cytospins of peripheral blood mononuclear cells (PBMCs) double stained for HER2 or EGFR and cytokeratin.Results
A total of 120 cycles were administered in 22 patients; median age was 62.5 years, 15 (68.2%) patients were post-menopausal and 20 (90.1%) had HER2-negative primary tumors. At the end of the second course, HER2-positive CTC counts decreased in 76.2% of patients; the median number of HER2-positive CTCs/patient also declined significantly (p = 0.013), however the decrease was significant only among patients presenting disease stabilization (p = 0.018) but not among those with disease progression during lapatinib treatment. No objective responses were observed. All CTC-positive patients harbored EGFR-positive CTCs on progression compared to 62.5% at baseline (p = 0.054). The ratio of EGFR-positive CTCs/total CTCs detected in all patients increased from 17.1% at baseline to 37.6% on progression, whereas the mean percentage of HER2-negative CTCs/patient increased from 2.4% to 30.6% (p = 0.03).Conclusions
The above results indicate that lapatinib is effective in decreasing HER2-positive CTCs in patients with MBC irrespectively of the HER2 status of the primary tumor and imply the feasibility of monitoring the molecular changes on CTCs during treatment with targeted agents.Trial Registration
Clinical trial.gov NCT00694252 相似文献63.
Evolution and biogeography of the endemic Roucela complex (Campanulaceae: Campanula) in the Eastern Mediterranean 下载免费PDF全文
Andrew A. Crowl Clayton J. Visger Guilhem Mansion Ralf Hand Hsin‐Hui Wu Georgia Kamari Dimitrios Phitos Nico Cellinese 《Ecology and evolution》2015,5(22):5329-5343
At the intersection of geological activity, climatic fluctuations, and human pressure, the Mediterranean Basin – a hotspot of biodiversity – provides an ideal setting for studying endemism, evolution, and biogeography. Here, we focus on the Roucela complex (Campanula subgenus Roucela), a group of 13 bellflower species found primarily in the eastern Mediterranean Basin. Plastid and low‐copy nuclear markers were employed to reconstruct evolutionary relationships and estimate divergence times within the Roucela complex using both concatenation and species tree analyses. Niche modeling, ancestral range estimation, and diversification analyses were conducted to provide further insights into patterns of endemism and diversification through time. Diversification of the Roucela clade appears to have been primarily the result of vicariance driven by the breakup of an ancient landmass. We found geologic events such as the formation of the mid‐Aegean trench and the Messinian Salinity Crisis to be historically important in the evolutionary history of this group. Contrary to numerous past studies, the onset of the Mediterranean climate has not promoted diversification in the Roucela complex and, in fact, may be negatively affecting these species. This study highlights the diversity and complexity of historical processes driving plant evolution in the Mediterranean Basin. 相似文献
64.
Georgios Hadjigeorgiou Efthimios Dardiotis Georgios Tsivgoulis Triantafyllos Doskas Damianos Petrou Nikolaos Makris Nikolaos Vlaikidis Thomas Thomaidis Athanasios Kyritsis Nikolaos Fakas Xoulietta Treska Clementine Karageorgiou Stefania Sotirli Christos Giannoulis Dimitra Papadimitriou Ioannis Mylonas Evaggelos Kouremenos George S. Vlachos Dimitrios Georgiopoulos Despoina Mademtzoglou Michalis Vikelis Elias Zintzaras 《PloS one》2015,10(10)
65.
Dimitrios Konstantinidis Filipa Pereira EvaMaria Geissen Kristina Grkovska Eleni Kafkia Paula Jouhten Yongkyu Kim Saravanan Devendran Michael Zimmermann Kiran Raosaheb Patil 《Molecular systems biology》2021,17(8)
Adaptive laboratory evolution has proven highly effective for obtaining microorganisms with enhanced capabilities. Yet, this method is inherently restricted to the traits that are positively linked to cell fitness, such as nutrient utilization. Here, we introduce coevolution of obligatory mutualistic communities for improving secretion of fitness‐costly metabolites through natural selection. In this strategy, metabolic cross‐feeding connects secretion of the target metabolite, despite its cost to the secretor, to the survival and proliferation of the entire community. We thus co‐evolved wild‐type lactic acid bacteria and engineered auxotrophic Saccharomyces cerevisiae in a synthetic growth medium leading to bacterial isolates with enhanced secretion of two B‐group vitamins, viz., riboflavin and folate. The increased production was specific to the targeted vitamin, and evident also in milk, a more complex nutrient environment that naturally contains vitamins. Genomic, proteomic and metabolomic analyses of the evolved lactic acid bacteria, in combination with flux balance analysis, showed altered metabolic regulation towards increased supply of the vitamin precursors. Together, our findings demonstrate how microbial metabolism adapts to mutualistic lifestyle through enhanced metabolite exchange. 相似文献
66.
Dimitrios Tsikas 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(2):133-148
Immunoaffinity chromatography (IAC), mass spectrometry and especially tandem mass spectrometry (MS/MS) represent the most efficient and reliable analytical techniques for specific isolation, unequivocal identification and accurate quantification of numerous natural and synthetic substances in biological samples. This review article focuses on the combined use of these outstanding methodologies in basic and clinical research and in life sciences for the quantitative analysis of low- and high-molecular mass biomarkers, drugs and toxins in urine, plasma or serum samples, in tissue and other biologicals systems published in the last decade. The analytes discussed in some detail include the biomarkers of oxidative stress 15(S)-8-iso-prostaglandin F2α {15(S)-8-iso-PGF2α} and 3-nitrotyrosine, the major urinary metabolite of the lipid mediators cysteinyl leukotrienes, i.e., the leukotriene E4 (LTE4), melatonin, and the major collagen type II neoepitope peptide in human urine. 相似文献
67.
Baeumlisberger D Arrey TN Rietschel B Rohmer M Papasotiriou DG Mueller B Beckhaus T Karas M 《Proteomics》2010,10(21):3905-3909
The applicability of the less specific protease elastase for the identification of membrane and cytosolic proteins has already been demonstrated. MALDI as ionization technique particularly favors the detection of basic and to a lesser extent of weakly acidic peptides, whereas neutral peptides often remain undetected. Moreover, peptides below 700 Da are routinely excluded. In the following study, the advantage of additional information gained from tandem mass tag zero labeled peptides and the resultant increase in sequence coverage was evaluated. Through derivatization with tandem mass tag reagents, peptide measurement within the standard mass range of the MALDI reflector mode is achievable due to the mass increase. Compared to the unlabeled sample, peptides exhibiting relatively low molecular masses, pI values or higher hydrophobicity could be identified. 相似文献
68.
The supramolecular assemblies of voltage-dependent anion channels in the native membrane 总被引:8,自引:0,他引:8
Voltage-dependent anion channels (VDACs) are major constituents of the outer mitochondrial membrane (OMM). These primary transporters of nucleotides, ions and metabolites mediate a substantial portion of the OMM molecular traffic. To study the native supramolecular organization of the VDAC, we have isolated, characterized and imaged OMMs from potato tubers. SDS-PAGE and mass spectrometry of OMMs revealed the presence of the VDAC isoforms POM34 and POM36, as well as the translocase of the OMM complex. Tubular two-dimensional crystals of the VDAC spontaneously formed after incubation of OMMs for two to three months at 4 degrees C. Transmission electron microscopy revealed an oblique lattice and unit cells housing six circular depressions arranged in a hexagon. Atomic force microscopy of freshly isolated OMMs demonstrated (i) the existence of monomers to tetramers, hexamers and higher oligomers of the VDAC and (ii) its spatial arrangement within the oligomers in the native membrane. We discuss the importance of the observed oligomerization for modulation of the VDAC function, for the binding of hexokinase and creatine kinase to the OMM and for mitochondria-mediated apoptosis. 相似文献
69.
Quiescent T lymphocytes containing latent human immunodeficiency virus (HIV) provide a long-lived viral reservoir. This reservoir may be the source of active infection that is reinitiated following the cessation of antiretroviral therapy. Therefore, it is important to understand the mechanisms involved in latent infection to develop new strategies to eliminate the latent HIV reservoir. We have previously demonstrated that latently infected quiescent lymphocytes can be generated during thymopoiesis in vivo in the SCID-hu mouse system. However, there is still a pressing need for an in vitro model of HIV latency in primary human cells. Here, we present a novel in vitro model that recapitulates key aspects of dormant HIV infection. Using an enhanced green fluorescent protein-luciferase fusion protein-containing reporter virus, we have generated a stable infection in primary human CD4(+) CD8(+) thymocytes in the absence of viral gene expression. T-cell activation induces a >200-fold induction of reporter activity. The induced reporter activity originates from a fully reverse-transcribed and integrated genome. We further demonstrate that this model can be useful to study long terminal repeat regulation, as previously characterized NF-kappaB response element mutations decrease the activation of viral gene expression. This model can therefore be used to study intricate molecular aspects of activation-inducible HIV infection in primary cells. 相似文献
70.
The calcein-AM (calcein-acetoxymethyl ester) method is a widely used technique that is supposed to assay the intracellular 'labile iron pool' (LIP). When cells in culture are exposed to this ester, it passes the plasma membrane and reacts with cytosolic unspecific esterases. One of the reaction products, calcein, is a fluorochrome and a hydrophilic alcohol to which membranes are non-permeable and which, consequently, is retained within the cytosol of cells. Calcein fluorescence is quenched following chelation of low-mass labile iron, and the degree of quenching gives an estimate of the amounts of chelatable iron. However, a requirement for the assay to be able to demonstrate cellular LIP in total is that such iron be localized in the cytosol and not in a membrane-limited compartment. For some time it has been known that a major part of cellular, redox-active, labile, low-mass iron is temporarily localized in the lysosomal compartment as a result of the autophagic degradation of ferruginous materials, such as mitochondrial complexes and ferritin. Even if some calcein-AM may escape cytosolic esterases and enter lysosomes to be cleaved by lysosomal acidic esterases, the resulting calcein does not significantly chelate iron at 相似文献