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51.
The biological activities of a series of mono- and oligosaccharides (beta-xylosides and alpha-glucosides) of 9-fluorenylmethanol were investigated together with mono-beta-galactoside and beta-glucoside of this aglycone, produced by biocatalytic routes. By using marine glycoside hydrolases and inexpensive donors such as maltose or xylan, access to mono-alpha-glucoside or mono-beta-xyloside of 9-fluorenylmethanol was obtained. Additionally, interesting polyglycoside derivatives were isolated. Biological testing indicated that in vitro treatment with these carbohydrate derivatives may influence the balance of cytokines in the environment of human peripheral blood mononuclear cells (PBMC), restricting the harmful effect of herpes simplex type 2 replication. In fact, these carbohydrate derivatives tested in WISH cells did not show any significant antiviral activity.  相似文献   
52.
Yeasts isolated from Italian beverages and foods (wine and cheeses) were identified as Saccharomyces cerevisiae and Debaryomyces hansenii by sequencing the D1/D2 domain of the 26S rRNA gene and differentiated, at strain level, by microsatellite PCR fingerprinting and RAPD-PCR.All the strains showed antioxidant activity, as demonstrated by their ability to scavenge the free radical diphenyl-1-picrylhydrazyl (DPPH). Furthermore, tested strains revealed high in vitro inhibitory activity against two model genotoxins, 4-nitroquinoline-1-oxide (4-NQO) and N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), as showed by short-term methods with different target cells: SOS-Chromotest with Escherichia coli PQ37 and Comet assay with HT-29 enterocytes. High inhibitory activity towards 4-NQO was associated with cell viability, while heat-inactivated cells showed a reduced antigenotoxic capability. Surprisingly, high inhibition of MNNG genotoxicity was observed even with heat-treated cells. Moreover, the strains able to inhibit the genotoxins induced some changes in the spectroscopic properties of the original compound. This result perfectly agrees with the information obtained by the two bioassays.Interestingly, strains characterized for antioxidant and antigenotoxic properties, also presented acid-bile tolerance, indicating that food autochthonous yeasts could be expected to reach gut in viable form and thus prevent genotoxin DNA damage in situ.  相似文献   
53.
Olive leaves extracts are a natural source of polyphenols, mainly oleuropein, widely considered to be potentially beneficial for health. This study focused on evaluation of the anti-tumoural activities of some oleuropein peracetylated derivatives, obtained with “green chemical” methodologies, against two human breast cancer cell lines. MCF-7 and T-47D cells were treated with oleuropein, peracetylated oleuropein, peracetylated aglycone and peracetylated hydroxytyrosol and the effects on growth and viability were investigated. Antioxidant effects were analysed after treatment with hydrogen peroxide. The peracetylated compounds exerted higher antiproliferative effects than oleuropein, by an arrest of cell cycle progression, associated with a strong antioxidant activity. Our results demonstrate that olive leaves, a by-product of olive manufacture, may provide a precious source of chemical derivatives, obtainable by peracetylation of oleuropein derivatives, which provide beneficial properties for human health.  相似文献   
54.
The objective of this study was to examine the Saccharomyces and non-Saccharomyces yeast populations involved in a spontaneous fermentation of a traditional high sugar must (Vino cotto) produced in central Italy. Molecular identification of a total of 78 isolates was achieved by a combination of PCR-RFLP of the 5.8S ITS rRNA region and sequencing of the D1/D2 domain of the 26S rRNA gene. In addition, the isolates were differentiated by RAPD-PCR. Only a restricted number of osmotolerant yeast species, i.e. Candida apicola, Candida zemplinina and Zygosaccharomyces bailii, were found throughout all the fermentation process, while Saccharomyces cerevisiae prevailed after 15 days of fermentation. A physiological characterization of isolates was performed in relation to the resistance to osmotic stress and ethanol concentration. The osmotolerant features of C. apicola, C. zemplinina and Z. bailii were confirmed, while S. cerevisiae strains showed three patterns of growth in response to different glucose concentrations (2%, 20%, 40% and 60% w/v). The ability of some C. apicola and C. zemplinina strains to grow at 14% v/v ethanol is noteworthy. The finding that some yeast biotypes with higher multiple stress tolerance can persist in the entire winemaking process suggests possible future candidates as starter for Vino cotto production.  相似文献   
55.
Abnormalities in RNA metabolism and alternative splicing (AS) are emerging as important players in complex disease phenotypes. In particular, accumulating evidence suggests the existence of pathogenic links between multiple sclerosis (MS) and altered AS, including functional studies showing that an imbalance in alternatively-spliced isoforms may contribute to disease etiology. Here, we tested whether the altered expression of AS-related genes represents a MS-specific signature. A comprehensive comparative analysis of gene expression profiles of publicly-available microarray datasets (190 MS cases, 182 controls), followed by gene-ontology enrichment analysis, highlighted a significant enrichment for differentially-expressed genes involved in RNA metabolism/AS. In detail, a total of 17 genes were found to be differentially expressed in MS in multiple datasets, with CELF1 being dysregulated in five out of seven studies. We confirmed CELF1 downregulation in MS (p = 0.0015) by real-time RT-PCRs on RNA extracted from blood cells of 30 cases and 30 controls. As a proof of concept, we experimentally verified the unbalance in alternatively-spliced isoforms in MS of the NFAT5 gene, a putative CELF1 target. In conclusion, for the first time we provide evidence of a consistent dysregulation of splicing-related genes in MS and we discuss its possible implications in modulating specific AS events in MS susceptibility genes.  相似文献   
56.
Nodal is a potent embryonic morphogen belonging to the TGF-β superfamily. Typically, it also binds to the ALK4/ActRIIB receptor complex in the presence of the co-receptor Cripto-1. Nodal expression is physiologically restricted to embryonic tissues and human embryonic stem cells, is absent in normal cells but re-emerges in several human cancers, including melanoma, breast, and colon cancer. Our aim was to obtain mAbs able to recognize Nodal on a major CBR (Cripto-Binding-Region) site and to block the Cripto-1-mediated signalling. To achieve this, antibodies were raised against hNodal(44–67) and mAbs generated by the hybridoma technology. We have selected one mAb, named 3D1, which strongly associates with full-length rhNodal (KD 1.4 nM) and recognizes the endogenous protein in a panel of human melanoma cell lines by western blot and FACS analyses. 3D1 inhibits the Nodal-Cripto-1 binding and blocks Smad2/3 phosphorylation. Data suggest that inhibition of the Nodal-Cripto-1 axis is a valid therapeutic approach against melanoma and 3D1 is a promising and interesting agent for blocking Nodal-Cripto mediated tumor development. These findings increase the interest for Nodal as both a diagnostic and prognostic marker and as a potential new target for therapeutic intervention.  相似文献   
57.
58.
Formyl peptide receptors (FPRs) are cell surface pattern recognition receptors (PRRs), belonging to the chemoattractant G protein-coupled receptors (GPCRs) family. They play a key role in the innate immune system, regulating both the initiation and the resolution of the inflammatory response. FPRs were originally identified as receptors with high binding affinity for bacteria or mitochondria N-formylated peptides. However, they can also bind a variety of structurally different ligands. Among FPRs, formyl peptide receptor-like 1 (FPRL1) is the most versatile, recognizing N-formyl peptides, non-formylated peptides, and synthetic molecules. In addition, according to the ligand nature, FPRL1 can mediate either pro- or anti-inflammatory responses. Hp(2-20), a Helicobacter pylori-derived, non-formylated peptide, is a potent FPRL1 agonist, participating in Helicobacter pylori-induced gastric inflammation, thus contributing to the related site or not-site specific diseases. The aim of this review is to provide insights into the role of FPRs in H. pylori-associated chronic inflammation, which suggests this receptor as potential target to mitigate both microbial and sterile inflammatory diseases.  相似文献   
59.
Fibromyalgia is a syndrome characterized by chronic and widespread musculoskeletal pain, often accompanied by other symptoms, such as fatigue, intestinal disorders and alterations in sleep and mood. It is estimated that two to eight percent of the world population is affected by fibromyalgia. From a medical point of view, this pathology still presents inexplicable aspects. It is known that fibromyalgia is caused by a central sensitization phenomenon characterized by the dysfunction of neuro-circuits, which involves the perception, transmission and processing of afferent nociceptive stimuli, with the prevalent manifestation of pain at the level of the locomotor system. In recent years, the pathogenesis of fibromyalgia has also been linked to other factors, such as inflammatory, immune, endocrine, genetic and psychosocial factors. A rheumatologist typically makes a diagnosis of fibromyalgia when the patient describes a history of pain spreading in all quadrants of the body for at least three months and when pain is caused by digital pressure in at least 11 out of 18 allogenic points, called tender points. Fibromyalgia does not involve organic damage, and several diagnostic approaches have been developed in recent years, including the analysis of genetic, epigenetic and serological biomarkers. Symptoms often begin after physical or emotional trauma, but in many cases, there appears to be no obvious trigger. Women are more prone to developing the disease than men. Unfortunately, the conventional medical therapies that target this pathology produce limited benefits. They remain largely pharmacological in nature and tend to treat the symptomatic aspects of various disorders reported by the patient. The statistics, however, highlight the fact that 90% of people with fibromyalgia also turn to complementary medicine to manage their symptoms.  相似文献   
60.
Mutations in the PSEN1 gene are the most common cause of autosomal dominant Alzheimer’s disease, and are characterized by a high phenotype variability. This study describes a five-generation family, with a prevalent late-onset of the disease and a high frequency of depression, in which a new missense mutation (c.789T > G, p.Cys263Trp) in exon 8 of the PSEN1 gene was found. Only the proband presented an early onset at the age of 45 with attention deficit, followed by spatial disorientation, psychiatric symptoms and parkinsonian signs. The other two cases had a late onset of the disease and a typical presentation with memory loss. Both were characterized by a high level of anxiety and depression. The disease course was different with signs of Lewy body dementia for the proband’s mother, and pyramidal involvement and a shorter disease duration for the proband’s maternal aunt. The other eight cases with late-onset dementia and three cases with a long history of depression have been reported in the family pedigree, underlying the high phenotype variability of PSEN1 mutations.  相似文献   
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