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排序方式: 共有612条查询结果,搜索用时 15 毫秒
1.
Benito Casu Giangiacomo Torri Margherita Legramandi Pier Giorgio Righetti 《Carbohydrate research》1982,104(2):299-308
The binding of heparin (Hep) and Hep fractions with oligo- and poly-(alkylenimines) having the general formula H2N(CH2-CHR-NH)nH, where R = H or Me, has been investigated by spectroscopy, by evaluating the competition of the amines and Methylene Blue for the anionic sites of Hep. The strongest-binding was observed at pH 3.5, with the essentially linear triethylenetetramine and the slightly branched tetraethylenepentamine giving the most stable complexes. For N (number of nitrogen atoms per molecule) >5, a decrease of the binding ability of the amines was observed. The apparent stoichiometry of the complexes was a function of the relative concentration of Hep and the amine, indicating an equilibrium between different types of complexes. Beef-lung Hep and a Hep fraction consisting mainly of trisulphated disaccharide blocks gave stronger complexes than the more heterogeneous, pigmucosal Hep and a Hep fraction of lower sulphate content. The results are interpreted in terms of polyelectrolyte-type associations involving sulphate groups on adjacent residues of the Hep chain and sequences of charged nitrogen atoms on the polyamine. 相似文献
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Margherita Cruciata Ciro Sannino Danilo Ercolini Maria L. Scatassa Francesca De Filippis Isabella Mancuso Antonietta La Storia Giancarlo Moschetti Luca Settanni 《Applied and environmental microbiology》2014,80(7):2050-2061
The microbial composition of artisan and industrial animal rennet pastes was studied by using both culture-dependent and -independent approaches. Pyrosequencing targeting the 16S rRNA gene allowed to identify 361 operational taxonomic units (OTUs) to the genus/species level. Among lactic acid bacteria (LAB), Streptococcus thermophilus and some lactobacilli, mainly Lactobacillus crispatus and Lactobacillus reuteri, were the most abundant species, with differences among the samples. Twelve groups of microorganisms were targeted by viable plate counts revealing a dominance of mesophilic cocci. All rennets were able to acidify ultrahigh-temperature-processed (UHT) milk as shown by pH and total titratable acidity (TTA). Presumptive LAB isolated at the highest dilutions of acidified milks were phenotypically characterized, grouped, differentiated at the strain level by randomly amplified polymorphic DNA (RAPD)-PCR analysis, and subjected to 16S rRNA gene sequencing. Only 18 strains were clearly identified at the species level, as Enterococcus casseliflavus, Enterococcus faecium, Enterococcus faecalis,
Enterococcus lactis, Lactobacillus delbrueckii, and Streptococcus thermophilus, while the other strains, all belonging to the genus Enterococcus, could not be allotted into any previously described species. The phylogenetic analysis showed that these strains might represent different unknown species. All strains were evaluated for their dairy technological performances. All isolates produced diacetyl, and 10 of them produced a rapid pH drop in milk, but only 3 isolates were also autolytic. This work showed that animal rennet pastes can be sources of LAB, mainly enterococci, that might contribute to the microbial diversity associated with dairy productions. 相似文献
4.
Gloria Ravegnini Giulia Sammarini Margherita Nannini Maria A. Pantaleo Guido Biasco Patrizia Hrelia 《Autophagy》2017,13(3):452-463
Autophagy and apoptosis are 2 fundamental biological mechanisms that may cooperate or be antagonistic, although both are involved in deciding the fate of cells in physiological or pathological conditions. These 2 mechanisms coexist simultaneously in cells and share common upstream signals and stimuli. Autophagy and apoptosis play pivotal roles in cancer development. Autophagy plays a key function in maintaining tumor cell survival by providing energy during unfavorable metabolic conditions through its recycling mechanism, and supporting the high energy requirement for metabolism and growth. This review focuses on gastrointestinal stromal tumors and cell death through autophagy and apoptosis, taking into account the involvement of both of these processes in tumor development and growth and as mechanisms of drug resistance. We also focus on the crosstalk between autophagy and apoptosis as an emerging field with major implications for the development of novel therapeutic options. 相似文献
5.
Margherita Cirillo Silengo Gianfranco Davi Giorgio Crua Piergiorgio Franceschini 《Human genetics》1978,42(3):323-326
Summary An 8-year-old male with mental retardation, speech difficulties, and minor congenital anomalies is presented. The clinical findings suggest the trisomy-8 syndrome. The karyotype indicates trisomy-8 mosaicism with trisomic as well as normal cell lines in blood lymphocytes. 相似文献
6.
Arun K. Ghosh Margherita Brindisi Yu-Chen Yen Emilio L. Cárdenas Jean-Rene Ella-Menye Nagaswamy Kumaragurubaran Xiangping Huang Jordan Tang Andrew D. Mesecar 《Bioorganic & medicinal chemistry letters》2017,27(11):2432-2438
We report the design and synthesis of a series of BACE1 inhibitors incorporating mono- and bicyclic 6-substituted 2-oxopiperazines as novel P1′ and P2′ ligands and isophthalamide derivative as P2-P3 ligands. Among mono-substituted 2-oxopiperazines, inhibitor 5a with N-benzyl-2-oxopiperazine and isophthalamide showed potent BACE1 inhibitory activity (Ki = 2 nM). Inhibitor 5g, with N-benzyl-2-oxopiperazine and substituted indole-derived P2-ligand showed a reduction in potency. The X-ray crystal structure of 5g-bound BACE1 was determined and used to design a set of disubstituted 2-oxopiperazines and bicyclic derivatives that were subsequently investigated. Inhibitor 6j with an oxazolidinone derivative showed a BACE1 inhibitory activity of 23 nM and cellular EC50 of 80 nM. 相似文献
7.
Marcella Barbarino Daniele Cesari Maria Bottaro Luca Luzzi Asadoor Namagerdi Franca Maria Bertolino Cristiana Bellan Fabrizio Proietti Pasquale Somma Mariacarolina Micheli Maria Margherita de Santi Raffaella Guazzo Luciano Mutti Luigi Pirtoli Piero Paladini Paola Indovina Antonio Giordano 《Journal of cellular and molecular medicine》2020,24(10):5565-5577
Malignant mesothelioma (MM) is an aggressive asbestos-related cancer of the serous membranes. Despite intensive treatment regimens, MM is still a fatal disease, mainly due to the intrinsic resistance to current therapies and the lack of predictive markers and new valuable molecular targets. Protein arginine methyltransferase 5 (PRMT5) inhibition has recently emerged as a potential therapy against methylthioadenosine phosphorylase (MTAP)-deficient cancers, in which the accumulation of the substrate 5'-methylthioadenosine (MTA) inhibits PRMT5 activity, thus sensitizing the cells to further PRMT5 inhibition. Considering that the MTAP gene is frequently codeleted with the adjacent cyclin-dependent kinase inhibitor 2A (CDKN2A) locus in MM, we assessed whether PRMT5 could represent a therapeutic target also for this cancer type. We evaluated PRMT5 expression, the MTAP status and MTA content in normal mesothelial and MM cell lines. We found that both administration of exogenous MTA and stable PRMT5 knock-down, by short hairpin RNAs (shRNAs), selectively reduced the growth of MTAP-deleted MM cells. We also observed that PRMT5 knock-down in MTAP-deficient MM cells reduced the expression of E2F1 target genes involved in cell cycle progression and of factors implicated in epithelial-to-mesenchymal transition. Therefore, PRMT5 targeting could represent a promising new therapeutic strategy against MTAP-deleted MMs. 相似文献
8.
Malakar Moumita Beruto Margherita Barba-Gonzalez Rodrigo 《Plant Cell, Tissue and Organ Culture》2022,149(3):503-522
Plant Cell, Tissue and Organ Culture (PCTOC) - Heliconia, also known as ‘False-Bird-of-Paradise’, is a genus of flowering plants in the monotypic family of Heliconiaceae.The genus... 相似文献
9.
Germani Margherita A. Elsysy Mokhles A. Toselli Moreno Rothwell Nikki Ghorab Mohamed A. Beaudry Randolph Einhorn Todd C. 《Plant Growth Regulation》2022,98(1):141-153
Plant Growth Regulation - Ethylene is an endogenous plant hormone associated with natural senescence and abscission of plant organs. Ethylene release from the degradation of 2-chloroethylphosphonic... 相似文献
10.
Caterina Longo Simonetta Piana Aimilios Lallas Elvira Moscarella Mara Lombardi Margherita Raucci Giovanni Pellacani Giuseppe Argenziano 《PloS one》2015,10(9)