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131.
Marco Caruso Claire T. Federici Mikeal L. Roose 《Molecular breeding : new strategies in plant improvement》2008,21(2):195-204
Simple sequence repeat (SSR) markers generated from expressed sequence tag (EST) sequences represent useful tools for genotyping
and their development is relatively easy because of the public availability of EST databases. We report design and application
of EST–SSRs to assess the level of genetic diversity among thirty-five asparagus cultivars and to fingerprint DePaoli, a new
variety released by University of California, Riverside. DNA was isolated from bulks of pooled cladophylls coming from five
plants of each variety to reduce the number of DNA extractions and PCR reactions. Allele frequencies were estimated from the
intensity of the bands in two bulks and two individual plant samples for each variety. Although asparagus varieties derive
from a limited germplasm pool, eight EST–SSR loci differentiated all of the analyzed cultivars. Moreover, UPGMA (unweighted
pair group method with arithmetic mean) and neighbor-joining trees, as well as principal components analysis separated the
cultivars into clusters corresponding to the geographical areas where they originated. 相似文献
132.
Michele Signore Romina Alfonsi Giulia Federici Simona Nanni Antonio Addario Lucia Bertuccini Aurora Aiello Anna Laura Di Pace Isabella Sperduti Giovanni Muto Alessandro Giacobbe Devis Collura Lidia Brunetto Giuseppe Simone Manuela Costantini Lucio Crin Stefania Rossi Claudio Tabolacci Marco Diociaiuti Tania Merlino Michele Gallucci Steno Sentinelli Rocco Papalia Ruggero De Maria Dsire Bonci 《Cell death & disease》2021,12(7)
Extracellular vesicles (EVs) and their cargo represent an intriguing source of cancer biomarkers for developing robust and sensitive molecular tests by liquid biopsy. Prostate cancer (PCa) is still one of the most frequent and deadly tumor in men and analysis of EVs from biological fluids of PCa patients has proven the feasibility and the unprecedented potential of such an approach. Here, we exploited an antibody-based proteomic technology, i.e. the Reverse-Phase Protein microArrays (RPPA), to measure key antigens and activated signaling in EVs isolated from sera of PCa patients. Notably, we found tumor-specific protein profiles associated with clinical settings as well as candidate markers for EV-based tumor diagnosis. Among others, PD-L1, ERG, Integrin-β5, Survivin, TGF-β, phosphorylated-TSC2 as well as partners of the MAP-kinase and mTOR pathways emerged as differentially expressed endpoints in tumor-derived EVs. In addition, the retrospective analysis of EVs from a 15-year follow-up cohort generated a protein signature with prognostic significance. Our results confirm that serum-derived EV cargo may be exploited to improve the current diagnostic procedures while providing potential prognostic and predictive information. The approach proposed here has been already applied to tumor entities other than PCa, thus proving its value in translational medicine and paving the way to innovative, clinically meaningful tools.Subject terms: Tumour biomarkers, Protein-protein interaction networks 相似文献
133.
When the diamines putrescine, cadaverine, cystamine and lanthionamine are oxidized by purified pig kidney diamine oxidase in the presence of NADH and either liver or yeast crystalline alcohol dehydrogenase, NADH is oxidized. Chromatographic evidence obtained in the case of putrescine and cystamine indicates the production of the respective hydroxy-amino compound. In the case of cystamine, the product of the reaction is mercapto-ethanol-cysteamine mixed disulfide which may represent a biological source for the production of mercaptoethanol used for other reactions. 相似文献
134.
135.
A simple and rapid method for the purification of glutathione S-transferase is described. The physical and kinetic properties of purified enzyme are reported. The protein is constituted of two identical subunits with a total molecular weight of 46,000 daltons. The isoelectric focusing of crude cytosol or purified preparation gives a single peak of activity with a pI of 7.1. The kinetic analysis shows a relatively strict substrate specificity. Only 1-chloro-2,4-dinitrobenzene is conjugated to reduced glutathione at an appreciable rate. The peroxidase activity of the enzyme with respect to cumene hydroperoxide as substrate is negligible. Hemin and bilirubin are competitive inhibitors of catalytic activity. 相似文献
136.
G Federici C Di Ilio P Sacchetta G Polidoro J V Bannister 《The International journal of biochemistry》1985,17(5):653-656
Glutathione S-transferase activity from human platelets was purified to homogeneity by affinity chromatography. The purified enzyme was found to be the acidic form and its molecular and catalytic properties were identical to acidic glutathione S-transferases purified from other human tissues. The purified platelet enzyme had no peroxidase activity and did not protect microsomes against peroxidation. 相似文献
137.
Enrico Casalone Carmine Di Ilio Giorgio Federici Mario Polsinelli 《Antonie van Leeuwenhoek》1988,54(4):367-375
Total glutathione content, glutathione peroxidase, glutathione transferase and glutathione reductase activities have been measured in 12 species of yeasts. All the strains tested contained glutathione, though in different amounts, as well as the above mentioned enzymes. To discriminate between the selenium-dependent and the selenium-independent form, glutathione peroxidase activity has been measured with both H2O2 and cumene hydroperoxide. Rhodotorula glutinis appeared to be the only strain in which the selenium-dependent form was not found, but this yeast exhibited the highest level of selenium-independent glutathione peroxidase activity as compared to the other strains. 相似文献
138.
C S Apperson B A Federici F R Tarver W Stewart 《Journal of invertebrate pathology》1992,60(3):219-228
Biotic and abiotic parameters associated with an epizootic of the fungus Coelomomyces punctatus in larval populations of the mosquito Anopheles quadrimaculatus were investigated for three mosquito breeding seasons (1986-1988) in two adjacent farm ponds in North Carolina. In the first pond, the prevalence of infected larvae averaged 42% (range 0-85%) for collections made weekly from May 1 to November 20, 1986, but larvae did not occur in this pond in 1987. Infection rates in the adjacent pond, sampled during the mosquito breeding seasons of 1987 and 1988, declined from 10.9% (range 0-27.5%) in 1987 to 2.5% (range 0-14.2%) in 1988. Correlation analyses between the number of female copepods and fungal infection rates in sentinel mosquitoes were significant (P < 0.01) for Acanthocyclops robustus but insignificant for eight other species. Infections obtained in sentinel larvae placed in the ponds for 3 hr intervals indicated that C. punctatus infected larvae around sundown. Infection rates for field-collected larvae increased with the stage of larval development. However, experiments with sentinel larvae showed that early instars were more susceptible to infection than later instars, suggesting that the higher infection rates in late instars resulted from individual larvae being infected by two or more zygotes during larval development. Standard multiple regression analyses, used to determine the relationship between seasonal infection rates and water chemistry, weather variables, and the abundance of early and late instar larvae, showed that the abundance of late instars was the only independent variable common to linear models. The models only accounted for 20 and 9% of the variation in larval infection rates for 1987 and 1988, respectively. These results indicate that of the parameters examined, the seasonal abundance of the copepod, A. robustus, was the most important factor (or variable) correlated with the prevalence of mosquito infection. 相似文献
139.
140.
Maurizio Petruccioli Paola Piccioni Federico Federici Mario Polsinelli 《FEMS microbiology letters》1995,128(2):107-111
Abstract Conidia of Penicillium variabile P16 were subjected to mutagenesis and selection for glucose oxidase production on media containing o -dianisidine. Studies of the relationship between dose of UV irradiation and conidial survival and frequency of mutation showed that the best frequency of positive mutation (17%) was obtained in correspondence to a conidial survival of 52%. Out of 54 overproducing mutants tested in shaken flasks, M-80.10 showed the highest level of glucose oxidase activity (127% higher than the wild-type). M-80.10 mutant, transferred every 15 days to fresh medium and tested monthly for 8 months, appeared stable. The time course of growth and enzyme production by the mutant M-80.10 showed an increase of the glucose oxidase activity in the culture medium up to 19 U ml−1 after 96 h of fermentation. 相似文献