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91.
Giacomo Pozzoli Hany E. Marei Asma Althani Alma Boninsegna Patrizia Casalbore Lionel N. J. L. Marlier Giulia Lanzilli Manuela Zonfrillo Giovanna Petrucci Bianca Rocca Pierluigi Navarra Alessandro Sgambato Carlo Cenciarelli 《Journal of cellular physiology》2019,234(9):15459-15471
Several clinical studies indicated that the daily use of aspirin or acetylsalicylic acid reduces the cancer risk via cyclooxygenases (Cox-1 and Cox-2) inhibition. In addition, aspirin-induced Cox-dependent and -independent antitumor effects have also been described. Here we report, for the first time, that aspirin treatment of human glioblastoma cancer (GBM) stem cells, a small population responsible for tumor progression and recurrence, is associated with reduced cell proliferation and motility. Aspirin did not interfere with cell viability but induced cell-cycle arrest. Exogenous prostaglandin E2 significantly increased cell proliferation but did not abrogate the aspirin-mediated growth inhibition, suggesting a Cox-independent mechanism. These effects appear to be mediated by the increase of p21 waf1 and p27 Kip1, associated with a reduction of Cyclin D1 and Rb1 protein phosphorylation, and involve the downregulation of key molecules responsible for tumor development, that is, Notch1, Sox2, Stat3, and Survivin. Our results support a possible role of aspirin as adjunctive therapy in the clinical management of GBM patients. 相似文献
92.
Thomas Noe Perry Hager Souabni Chiara Rapisarda Rémi Fronzes Fabrice Giusti Jean-Luc Popot Manuela Zoonens Francesca Gubellini 《生物化学与生物物理学报:生物膜》2019,1861(2):466-477
Membrane protein (MP) complexes play key roles in all living cells. Their structural characterisation is hampered by difficulties in purifying and crystallising them. Recent progress in electron microscopy (EM) have revolutionised the field, not only by providing higher-resolution structures for previously characterised MPs but also by yielding first glimpses into the structure of larger and more challenging complexes, such as bacterial secretion systems. However, the resolution of pioneering EM structures may be difficult and their interpretation requires clues regarding the overall organisation of the complexes. In this context, we present BAmSA, a new method for localising transmembrane (TM) regions in MP complexes, using a general procedure that allows tagging them without resorting to neither genetic nor chemical modification. Labels bound to TM regions can be visualised directly on raw negative-stain EM images, on class averages, or on three-dimensional reconstructions, providing a novel strategy to explore the organisation of MP complexes. 相似文献
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94.
Silas Bergen Manuela M. Huso Adam E. Duerr Melissa A. Braham Todd E. Katzner Sara Schmuecker Tricia A. Miller 《Ecology and evolution》2022,12(2)
- Recent advances in digital data collection have spurred accumulation of immense quantities of data that have potential to lead to remarkable ecological insight, but that also present analytic challenges. In the case of biologging data from birds, common analytical approaches to classifying movement behaviors are largely inappropriate for these massive data sets.
- We apply a framework for using K‐means clustering to classify bird behavior using points from short time interval GPS tracks. K‐means clustering is a well‐known and computationally efficient statistical tool that has been used in animal movement studies primarily for clustering segments of consecutive points. To illustrate the utility of our approach, we apply K‐means clustering to six focal variables derived from GPS data collected at 1–11 s intervals from free‐flying bald eagles (Haliaeetus leucocephalus) throughout the state of Iowa, USA. We illustrate how these data can be used to identify behaviors and life‐stage‐ and age‐related variation in behavior.
- After filtering for data quality, the K‐means algorithm identified four clusters in >2 million GPS telemetry data points. These four clusters corresponded to three movement states: ascending, flapping, and gliding flight; and one non‐moving state: perching. Mapping these states illustrated how they corresponded tightly to expectations derived from natural history observations; for example, long periods of ascending flight were often followed by long gliding descents, birds alternated between flapping and gliding flight.
- The K‐means clustering approach we applied is both an efficient and effective mechanism to classify and interpret short‐interval biologging data to understand movement behaviors. Furthermore, because it can apply to an abundance of very short, irregular, and high‐dimensional movement data, it provides insight into small‐scale variation in behavior that would not be possible with many other analytical approaches.
95.
Enrica Cappellozza Federico Boschi Maddalena Sguizzato Elisabetta Esposito Rita Cortesi Manuela Malatesta Laura Calderan 《European journal of histochemistry : EJH》2022,66(1)
The investigation of the absorption of drug delivery systems, designed for the transport of therapeutic molecules inside the body, could be relatively simplified by the fluorophore association and tracking by means of bio-imaging techniques (i.e., optical in vivo imaging or confocal and multiphoton microscopy). However, when a fluorescence signal comes out from the skin, its specific detection can be problematic. Skin high autofluorescence can hinder the observation of administered exogenous fluorophores conjugated to drug delivery systems, making it more challenging to detect their biodistribution. In the present study, we have developed a method based on the spectrofluorometric analysis of skin samples to discriminate the fluorescent signal coming from administered fluorescent molecules from the background. Moreover, we gave a semi-quantitative evaluation of the signal intensity. Thus, we distinguished two gel formulations loading the fluorophore rhodamine B (called GEL RHO and GEL SLN-RHO). The two formulations of gels, one of which containing solid lipid nanoparticles (GEL RHO-SLN), were administered on skin explants incubated in a bioreactor, and the penetration was evaluated at different time points (2 and 6 hours). Cryostatic sections of skin samples were observed with confocal laser scanning microscopy, and a spectrofluorometric analysis was performed. Significantly higher signal intensity in the samples administered with SLN-RHO GEL, with a preferential accumulation in the hair bulbs, was found. Reaching also the deeper layers of the hair shaft after 6 hours, the solid lipid nanoparticles thickened with polymer represent a suitable drug delivery system for transcutaneous administration.Key words: Organ culture, bioreactor, transcutaneous biodistribution, spectrofluorimetric analysis 相似文献
96.
Manuela de O. Ramalho Leonardo Menino Rodrigo F. Souza Dbora Y. Kayano Juliana M. C. Alves Ricardo Harakava Victor H. Nagatani Otvio G. M. Silva Odair C. Bueno Maria S. C. Morini 《Genetics and molecular biology》2022,45(1)
In South America, Solenopsis saevissima and S. invicta are the most common fire ants. Nests are founded in areas under anthropic interference like urban or rural areas, but S. invicta is found preferentially in those with the greatest anthropic interference. However, we do not know the rates at which they exist in anthropized areas next to high density of native vegetation. Areas with 60 to 90% of native Atlantic Forest were selected to verify the occurrence of both species in rural and urban areas. We investigated the molecular diversity and applied the reconstruction of the ancestral state analysis for each species. A total of 186 nests were analyzed and we found that the two species had the same proportion in the urban area. However, S. saevissima had a higher rate of prevalence in the rural area, in addition to having a greater number of haplotypes and ancestry associated with this type of habitat for the region. S. invicta had the same number of haplotypes in both rural and urban regions, and less haplotypic diversity. We conclude that S. saevissima is a species typically associated with rural areas and S. invicta, although present, is not dominant in urban areas. Keywords: Biodiversity, haplotype diversity, DNA barcoding, mtDNA 相似文献
97.
Manuela G. Neuman Helmut K. Seitz Rolf Teschke Stephen Malnick Kamisha L. Johnson-Davis Lawrence B. Cohen Anit German Nicolas Hohmann Bernhardo Moreira George Moussa Mihai Opris 《Current issues in molecular biology》2022,44(3):1294
Hepatic cells are sensitive to internal and external signals. Ethanol is one of the oldest and most widely used drugs in the world. The focus on the mechanistic engine of the alcohol-induced injury has been in the liver, which is responsible for the pathways of alcohol metabolism. Ethanol undergoes a phase I type of reaction, mainly catalyzed by the cytoplasmic enzyme, alcohol dehydrogenase (ADH), and by the microsomal ethanol-oxidizing system (MEOS). Reactive oxygen species (ROS) generated by cytochrome (CYP) 2E1 activity and MEOS contribute to ethanol-induced toxicity. We aimed to: (1) Describe the cellular, pathophysiological and clinical effects of alcohol misuse on the liver; (2) Select the biomarkers and analytical methods utilized by the clinical laboratory to assess alcohol exposure; (3) Provide therapeutic ideas to prevent/reduce alcohol-induced liver injury; (4) Provide up-to-date knowledge regarding the Corona virus and its affect on the liver; (5) Link rare diseases with alcohol consumption. The current review contributes to risk identification of patients with alcoholic, as well as non-alcoholic, liver disease and metabolic syndrome. Additional prevalence of ethnic, genetic, and viral vulnerabilities are presented. 相似文献
98.
Metabolic engineering of the early non-mevalonate terpenoid pathway of Escherichia coli was carried out to increase the supply of prenyl pyrophosphates as precursor for carotenoid production. Transformation with the genes dxs for over-expression of 1-deoxy-d-xylulose 5-phosphate synthase, dxr for 1-deoxy-d-xylulose 5-phosphate reductoisomerase and idi encoding an isopentenyl pyrophosphate stimulated carotenogenesis up to 3.5-fold. Co-transformation of idi with either dxs or dxr had an additive effect on ß-carotene and zeaxanthin production which reached 1.6 mg g–1 dry wt. 相似文献
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100.