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排序方式: 共有2997条查询结果,搜索用时 15 毫秒
71.
72.
Elena Bresciani Nicola Squillace Valentina Orsini Roberta Piolini Laura Rizzi Laura Molteni Ramona Meanti Alessandro Soria Giuseppe Lapadula Alessandra Bandera Andrea Gori Paolo Bonfanti Robert John Omeljaniuk Vittorio Locatelli Antonio Torsello 《International journal of molecular sciences》2022,23(7)
Combined AntiRetroviral Treatments (cARTs) used for HIV infection may result in varied metabolic complications, which in some cases, may be related to patient genetic factors, particularly microRNAs. The use of monozygotic twins, differing only for HIV infection, presents a unique and powerful model for the controlled analysis of potential alterations of miRNAs regulation consequent to cART treatment. Profiling of 2578 mature miRNA in the subcutaneous (SC) adipose tissue and plasma of monozygotic twins was investigated by the GeneChip® miRNA 4.1 array. Real-time PCR and ddPCR experiments were performed in order to validate differentially expressed miRNAs. Target genes of deregulated miRNAs were predicted by the miRDB database (prediction score > 70) and enrichment analysis was carried out with g:Profiler. Processes in SC adipose tissue most greatly affected by miRNA up-regulation included (i) macromolecular metabolic processes, (ii) regulation of neurogenesis, and (iii) protein phosphorylation. Furthermore, KEGG analysis revealed miRNA up-regulation involvement in (i) insulin signaling pathways, (ii) neurotrophin signaling pathways, and (iii) pancreatic cancer. By contrast, miRNA up-regulation in plasma was involved in (i) melanoma, (ii) p53 signaling pathways, and (iii) focal adhesion. Our findings suggest a mechanism that may increase the predisposition of HIV+ patients to insulin resistance and cancer. 相似文献
73.
Davide Loizzo Savio Domenico Pandolfo Devin Rogers Clara Cerrato Nicola Antonio di Meo Riccardo Autorino Vincenzo Mirone Matteo Ferro Camillo Porta Alessandro Stella Cinzia Bizzoca Leonardo Vincenti Marco Spilotros Monica Rutigliano Michele Battaglia Pasquale Ditonno Giuseppe Lucarelli 《International journal of molecular sciences》2022,23(7)
Autophagy is a complex process involved in several cell activities, including tissue growth, differentiation, metabolic modulation, and cancer development. In prostate cancer, autophagy has a pivotal role in the regulation of apoptosis and disease progression. Several molecular pathways are involved, including PI3K/AKT/mTOR. However, depending on the cellular context, autophagy may play either a detrimental or a protective role in prostate cancer. For this purpose, current evidence has investigated how autophagy interacts within these complex interactions. In this article, we discuss novel findings about autophagic machinery in order to better understand the therapeutic response and the chemotherapy resistance of prostate cancer. Autophagic-modulation drugs have been employed in clinical trials to regulate autophagy, aiming to improve the response to chemotherapy or to anti-cancer treatments. Furthermore, the genetic signature of autophagy has been found to have a potential means to stratify prostate cancer aggressiveness. Unfortunately, stronger evidence is needed to better understand this field, and the application of these findings in clinical practice still remains poorly feasible. 相似文献
74.
Mariarenata Sessa Alessandro A. Casazza Patrizia Perego Rong Tsao Giovanna Ferrari Francesco Donsì 《Food and Bioprocess Technology》2013,6(10):2609-2620
Phenolic compounds were extracted from grape marc by means of high pressure and temperature extraction. In order to increase their dispersability in the aqueous phase, the polyphenolic extracts were encapsulated at a final concentration of 0.1 % (w/w) in nanoemulsion-based delivery systems, which were formulated with natural ingredients, using either a liquid (sunflower oil) or a solid (palm oil) lipid phase, as well as the combination of a hydrophilic and hydrophobic emulsifier, and were produced by high-pressure homogenization. The delivery systems were characterized in terms of physicochemical stability under accelerated ageing (storage at 4 °C, 30 °C, and 55 °C for 14 days), by recording the evolution of the mean droplet size, the creaming index as well as the UV–vis absorption spectra of the encapsulated polyphenols. The antioxidant activity of the encapsulated extracts was measured with two different chemical assays (FRAP and ORAC) and a cellular antioxidant assay. Sunflower oil-based nanoemulsions resulted to be the most physically and chemically stable, with no significant variation of the mean droplet size and no degradation of the encapsulated compounds under the different conditions tested. The FRAP and ORAC assays showed that the antioxidant compounds, when encapsulated, are as available as unencapsulated polyphenols in scavenging the peroxyl radicals (ORAC), but are less available in reducing the ferric tripyridyltriazine complexes (FRAP). Remarkably, the cellular antioxidant activity was significantly higher for the encapsulated grape marc polyphenols than for the unencapsulated ones, suggesting the fundamental role of the nanoemulsions in favoring the delivery through the biological membranes. 相似文献
75.
Nicoletta Braidotti Maria Augusta do R. B. F. Lima Michele Zanetti Alessandro Rubert Catalin Ciubotaru Marco Lazzarino Orfeo Sbaizero Dan Cojoc 《International journal of molecular sciences》2022,23(8)
The connection between cytoskeleton alterations and diseases is well known and has stimulated research on cell mechanics, aiming to develop reliable biomarkers. In this study, we present results on rheological, adhesion, and morphological properties of primary rat cardiac fibroblasts, the cytoskeleton of which was altered by treatment with cytochalasin D (Cyt-D) and nocodazole (Noc), respectively. We used two complementary techniques: quartz crystal microbalance (QCM) and digital holographic microscopy (DHM). Qualitative data on cell viscoelasticity and adhesion changes at the cell–substrate near-interface layer were obtained with QCM, while DHM allowed the measurement of morphological changes due to the cytoskeletal alterations. A rapid effect of Cyt-D was observed, leading to a reduction in cell viscosity, loss of adhesion, and cell rounding, often followed by detachment from the surface. Noc treatment, instead, induced slower but continuous variations in the rheological behavior for four hours of treatment. The higher vibrational energy dissipation reflected the cell’s ability to maintain a stable attachment to the substrate, while a cytoskeletal rearrangement occurs. In fact, along with the complete disaggregation of microtubules at prolonged drug exposure, a compensatory effect of actin polymerization emerged, with increased stress fiber formation. 相似文献
76.
Ferracin LM Fier CB Vieira ML Monteiro-Vitorello CB Varani Ade M Rossi MM Müller-Santos M Taniwaki MH Thie Iamanaka B Fungaro MH 《International journal of food microbiology》2012,155(3):137-145
In silico comparison of 34 putative pks genes in Aspergillus niger strain CBS 513.88 versus A. niger strain ATCC 1015 genome revealed significant nucleotide identity (>95% covering a minimum of 99% of the gene sequence) for 31 of these genes (approximately 91%). A. niger CBS 513.88 harbors three putative pks genes (An01g01130, An11g05940, and An15g07920), for which nucleotide identity was not found in A. niger ATCC 1015. To compare the results of the in silico analysis with the in vivo situation, experimental data were obtained for a large number of A. niger strains obtained from different substrates and geographical regions. Three putative pks genes that were found to be variable between the two A. niger strains using bioinformatics tools were in fact strain-specific genes based on experimental data. The PCR amplification signals for the An01g01130, An11g05940, and An15g07920 pks genes were detected in only 97%, 71%, and 26% of the strains, respectively. Southern blot analyses confirmed the PCR data. Because one of the strain-specific pks genes (An15g07920) is located in a putative ochratoxin cluster, we focused our investigation on that region. We assessed the ochratoxin production capability of the 119 A. niger strains and found a positive association between the presence of this pks gene and the capability of the respective strain to produce ochratoxin. 相似文献
77.
Berardinelli A Cevoli C Silaghi FA Fabbri A Ragni L Giunchi A Bassi D 《Journal of food science》2010,75(7):E462-E468
Abstract: The nondestructive assessment of apricot fruit quality (Bora cultivar) was carried out by means of FT-NIR reflectance spectroscopy in the wavenumber range 12000 to 4000 cm−1. Samples were harvested at four different ripening stages and scanned by a fiber optical probe immediately after harvesting and after a storage of 3 d (2 d at 4 °C and 1 d at 18 °C); the flesh firmness (FF), the soluble solids content (SSC), the acidity (A), and the titratable acidity (malic and citric acids) were then measured by destructive methods. Soft independent modeling of class analogy (SIMCA) analysis was used to classify spectra according to the ripening stage and the storage: partial least squares regression (PLS) models to predict FF, SSC, A, and the titratable acidity were also set-up for both just harvested and stored apricots. Spectral pretreatments and wavenumber selections were conducted on the basis of explorative principal component analysis (PCA). Apricot spectra were correctly classified in the right class with a mean classification rate of 87% (range: 80% to 100%). Test set validations of PLS models showed R2 values up to 0.620, 0.863, 0.842, and 0.369 for FF, SSC, A, and the titratable acidity, respectively. The best models were obtained for the SSC and A and are suitable for rough screening; a lower power prediction emerged for the other maturity indices and the relative predictive models are not recommended. Practical Application : The results of the study could be used as a tool for the assessment of the ripening stage during the harvest and the quality during the postharvest storage of apricot fruits. 相似文献
78.
Maja Mikulic‐Petkovsek Franci Stampar Robert Veberic Helena Sircelj 《Journal of food science》2016,81(8):C1928-C1937
Sugars, organic acids, carotenoids, tocopherols, chlorophylls, and phenolic compounds were quantified in fruit of 4 wild growing Prunus species (wild cherry, bird cherry, blackthorn, and mahaleb cherry) using HPLC‐DAD‐MSn. In wild Prunus, the major sugars were glucose and fructose, whereas malic and citric acids dominated among organic acids. The most abundant classes of phenolic compounds in the analyzed fruit species were anthocyanins, flavonols, derivatives of cinnamic acids, and flavanols. Two major groups of anthocyanins measured in Prunus fruits were cyanidin‐3‐rutinoside and cyanidin‐3‐glucoside. Flavonols were represented by 19 derivatives of quercetin, 10 derivatives of kaempferol, and 2 derivatives of isorhamnetin. The highest total flavonol content was measured in mahaleb cherry and bird cherry, followed by blackthorn and wild cherry fruit. Total phenolic content varied from 2373 (wild cherry) to 11053 mg GAE per kg (bird cherry) and ferric reducing antioxidant power antioxidant activity from 7.26 to 31.54 mM trolox equivalents per kg fruits. 相似文献
79.
Alessandro Grandini Daniela Summa Stefania Costa Raissa Buzzi Elena Tamburini Gianni Sacchetti Alessandra Guerrini 《International journal of molecular sciences》2022,23(8)
Phytopathogenic fungi are among the main causes of productivity losses in agriculture. To date, synthetic chemical pesticides, such as hydroxyanilides, anilinopyrimidines and azole derivatives, represent the main treatment tools for crop plant defence. However, the large and uncontrolled use of these substances has evidenced several side effects, namely the resistance to treatments, environmental damage and human health risks. The general trend is to replace chemicals with natural molecules in order to reduce these side effects. Moreover, the valorisation of agri-food industry by-products through biotransformation processes represents a sustainable alternative to chemical synthesis in several sectors. This research is aimed at comparing the anti-phytopathogenic activity of waste bovine and porcine bile with secosteroids obtained by biotransformation of bile acids with Rhodococcus strains. The ultimate goal is to apply these natural products on food crops affected by phytopathogenic fungi. 相似文献
80.
Jean-Pierre Martins Louis Doceul Sbastien Marol Elise Delchi Jean-Jacques Cordier Bruno Levesy Alessandro Tesini Emanuela Ciattaglia Richard Tivey Ren Gillier Christophe Abbes 《Fusion Engineering and Design》2009,84(7-11):1268-1275
In the field of the ITER port plug engineering and integration task, CEA has contributed to define proposals concerning the port plugs vacuum sealing interface with the vessel flange and the equatorial plug handling.The 2001 baseline vacuum flange sealing consisted of TIG welding of a 316L strip plate on to U shapes. This arrangement presented some issues like welding access, implementation of tools, lip consumption, complex local leak test, continuous leak checking. Therefore, an alternate sealing solution based on the use of metallic gaskets is proposed. The different technical aspects are discussed to explain how this design can simplify the maintenance and deal with safety and vacuum requirements.The design of the mechanical attachment and vacuum sealing of the plug has constantly evolved, but the associated remote handling equipment was not systematically reviewed. An update of the cask and maintenance procedure was studied in order to design it in accordance with the last generic plug flange design. This includes a concept of a gripping system that uses the plug flange bolting area and, to help the remote handling process, a cantilever assisting system is suggested to increase the reliability of the transfer operation between vacuum vessel and cask. 相似文献