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21.
Objectives: Although emerging data suggest that zoledronic acid (Zol) may have different anti‐tumour activities against a broad range of cancers, its effects on lung cancer remain largely unknown. The aim of this study was to evaluate in vitro the anti‐tumoural and anti‐angiogenetic effect of zoledronic acid in non‐small‐cell lung cancer (NSCLC) cells. Material and methods: We treated A549 NSCLC cells with zoledronic acid to investigate survival, cell cycle activity, anti‐angiogenic activity and apoptotic responses to it. Results: We observed that highest Zol concentration (100 μm ) caused arrest in G1 phase of the cell cycle and also induced different percentages of apoptosis in presence (0.9% versus 4.4%) or absence (2.4% versus 28.5%) of serum (P = 0.0001). Zol concentration from 5 to 100 μm for 2 days induced significant concentration‐dependent cell death in adherent cells. Furthermore, Zol (10–100 μm ) induced dose‐dependent reduction both of mRNA and protein expression of VEGF associated with parallel decrease in VEGF secretion in the culture medium. Conclusion: Taken together, these results support a possible anti‐cancer and anti‐angiogenetic activity of Zol. Our data may not only provide a basis for the clinical use of this drug as preventive agent of bone metastases but also suggest that Zol deserves attention as an anti‐cancer agent in non‐small‐cell lung cancer.  相似文献   
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Blinks and saccades cause transient interruptions of visual input. To investigate how such effects influence our perceptual state, we analyzed the time courses of blink and saccade rates in relation to perceptual switching in the Necker cube. Both time courses of blink and saccade rates showed peaks at different moments along the switching process. A peak in blinking rate appeared 1,000 ms prior to the switching responses. Blinks occurring around this peak were associated with subsequent switching to the preferred interpretation of the Necker cube. Saccade rates showed a peak 150 ms prior to the switching response. The direction of saccades around this peak was predictive of the perceived orientation of the Necker cube afterwards. Peak blinks were followed and peak saccades were preceded by transient parietal theta band activity indicating the changing of the perceptual interpretation. Precisely-timed blinks, therefore, can initiate perceptual switching, and precisely-timed saccades can facilitate an ongoing change of interpretation.  相似文献   
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We report a procedure for the virtual reconstruction of incomplete human bones applicable to skeletal remains from archaeological excavations or to reconstructive and prosthetic surgery. To test the procedure, we reconstructed a fragmented left clavicle on the basis of the contralateral clavicle. The procedure involved 3‐D laser scanner acquisition of the left clavicle (complete but broken into two parts), the same manually reconstructed bone, and the intact right clavicle, which was mirror‐imaged and used as a reference for the reconstruction of the whole left clavicle. Because it was not possible to recognize homologous anatomical landmarks, on the two reference models (a mirror‐image copy of the right clavicle and the main fragment of the left), we identified three grids with an increasing number of corresponding landmarks, which constituted the framework of the deformation process. The three reconstructed digital models of the clavicle closely approximated the model of the original clavicle. They also showed that an increasing number of landmarks did not significantly improve the reconstructed model. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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In this paper the oxidation of milled wood lignin (MWL), catalysed by three enzymes, i.e. laccase, tyrosinase and horseradish peroxidase (HRP) was studied. The oxidation was followed by measuring the consumption of O2 during laccase and tyrosinase treatment and of H2O2 during HRP treatment. Both laccase and HRP were found to oxidise lignin effectively, whereas the effect of tyrosinase was negligible. The changes in MWL molecular-weight distributions caused in the reactions were analysed by gel permeation chromatography. Both laccase and HRP treatments were found to polymerise MWL. Peroxidase treatment was found to decrease the amount of phenolic hydroxyls in MWL, whereas no such effect could be detected in the laccase-treated sample. Both laccase and HRP treatments were, however, found to increase the amount of conjugated structures in MWL. The formation of phenoxy radicals during the treatments was studied by electron paramagnetic resonance spectroscopy. Phenoxy radicals were detected in both laccase and HRP-treated samples. The amount of the formed phenoxy radicals was found to be essentially constant during the detected time (i.e. 20–120 min after the addition of enzyme).  相似文献   
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Single cell gel electrophoresis (SCGE), also known as comet assay is a widely used method to detect DNA damage. Its use is nonetheless subjected to some pitfalls, due to differences in experimental set-up, to operator-dependent variability and to quantification of the comets, which is usually accomplished by visual scoring or by image-analysis software. Biological variability in the extent of DNA damage must be taken into account particularly regarding in vivo studies. In the present paper we propose an improved methodology where major features are: a) cryopreservation of lymphocytes collected at different time points and simultaneous analysis in a single run; b) use of an internal control on each slide; c) development of a custom-made software with semi - automated image analysis in order to overcome operator dependent variability. Cryopreservation was accomplished by storing lymphocytes in liquid nitrogen in a solution commonly used for preserving vital cells to be reinfused. We found that this procedure did not alter DNA after 2 and 4 months of storage. The use of quality control from a batch of aliquoted lymphocytes from a healthy donor on each slide, enabled to highlight possible experimental anomalies as well as verify inter-experimental variability. Moreover, by using a newly developed software able to automatically recognise comets we minimised operator-dependent variability in the scoring process. This improved methodology is proposed for longitudinal in vivo studies and in the present work its application made it possible to assess a significant increase of DNA in pediatric Down Syndrome patients compared to healthy controls of the same age.  相似文献   
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Phenotypic modulation of vascular smooth muscle cells (SMCs) in atherosclerosis and restenosis involves responses to the surrounding microenvironment. SMCs obtained by enzymatic digestion from tunica media of newborn, young adult (YA) and old rats and from the thickened intima (TI) and underlying media of young adult rat aortas 15 days after ballooning were entrapped in floating populated collagen lattice (PCL). TI-SMCs elongated but were poor at PCL contraction and remodeling and expressed less alpha2 integrin compared to other SMCs that appeared more dendritic. During early phases of PCL contraction, SMCs showed a marked decrease in the expression of alpha-smooth muscle actin and myosin. SMCs other than TI-SMCs required 7 days to re-express alpha-smooth muscle actin and myosin. Only TI-SMCs in PCL were able to divide in 48 h, with a greater proportion in S and G2-M cell cycle phases compared to other SMCs. Anti-alpha2 integrin antibody markedly inhibited contraction but not proliferation in YA-SMC-PLCs; anti-alpha1 and anti-alpha2 integrin antibodies induced a similar slight inhibition in TI-SMC-PCLs. Finally, TI-SMCs rapidly migrated from PCL on plastic reacquiring their epithelioid phenotype. Heterogeneity in proliferation and cytoskeleton as well the capacity to remodel the extracellular matrix are maintained, when SMCs are suspended in PCLs.  相似文献   
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Ruga  Luigia  Orlandi  Fabio  Fornaciari  Marco 《Aerobiologia》2021,37(2):363-372

The conservation actions towards artworks holding a common patrimony for the community are of primary importance, but also those related to their "container" as museums, libraries or archives are to consider. Fungal spores and bacteria carried by air flows to the artwork surface can colonize it causing biodeterioration through physical and/or chemical alterations of the materials with the irreversible loss of their value. The quality control of the indoor air surrounding the historic building is essential, as well as for the protection and conservation of the artwork, also for the protection of the health of operators and visitors. The aim of this study was to monitor airborne fungal particles, through volumetric spore traps, for improving the knowledge about the conservation and protection of artworks in the museum environment analysing the principal relationships between indoor environmental conditions and potentially biodeteriogen fungal spore growth. The evidence of no significant relationships between spore concentrations and environmental conditions recorded inside the different expositive rooms testified the regular and correct maintenance of the air conditioning system inside the considered building (National Gallery of Umbria, central Italy). Moreover, in a specific museum room a significant spore concentration decreasing trend was recorded mainly due to a structural modification in the same building.

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