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31.
Grape seeds (GS) are one of the most important by-products of the winery and grape juice industry. GS contain a vast array of health-giving metabolites, including several polyphenols known for their remarkable antioxidant activity. In this study, it has been evaluated the nutraceutical potential of seeds from 15 grapevine cultivars/clones in terms of total phenols, monomeric, dimer, polymeric, gallate esters flavan 3-ols composition and in vitro antiradical activity. Considerable quali-quantitative differences in polyphenol content and AA had been observed among GS from different cultivars/clones collected in 2013 and 2014. In most of the investigated cultivars/clones, the better values of TP, FL and AA were recorded in GS collected in 2014. The polymeric procyanidins were significantly higher in 2014 in all the cultivars, while the gallate esters were significantly higher in 2013. These differences can be attributed to different climatic conditions in 2013 and 2014. In conclusion, the data here reported help to identify the best source of GS for the recovery of bioactive polyphenols and to valorize these waste materials. 相似文献
32.
Roberto Berni Canani Naseer Sangwan Andrew T Stefka Rita Nocerino Lorella Paparo Rosita Aitoro Antonio Calignano Aly A Khan Jack A Gilbert Cathryn R Nagler 《The ISME journal》2016,10(3):742-750
Dietary intervention with extensively hydrolyzed casein formula supplemented with Lactobacillus rhamnosus GG (EHCF+LGG) accelerates tolerance acquisition in infants with cow''s milk allergy (CMA). We examined whether this effect is attributable, at least in part, to an influence on the gut microbiota. Fecal samples from healthy controls (n=20) and from CMA infants (n=19) before and after treatment with EHCF with (n=12) and without (n=7) supplementation with LGG were compared by 16S rRNA-based operational taxonomic unit clustering and oligotyping. Differential feature selection and generalized linear model fitting revealed that the CMA infants have a diverse gut microbial community structure dominated by Lachnospiraceae (20.5±9.7%) and Ruminococcaceae (16.2±9.1%). Blautia, Roseburia and Coprococcus were significantly enriched following treatment with EHCF and LGG, but only one genus, Oscillospira, was significantly different between infants that became tolerant and those that remained allergic. However, most tolerant infants showed a significant increase in fecal butyrate levels, and those taxa that were significantly enriched in these samples, Blautia and Roseburia, exhibited specific strain-level demarcations between tolerant and allergic infants. Our data suggest that EHCF+LGG promotes tolerance in infants with CMA, in part, by influencing the strain-level bacterial community structure of the infant gut. 相似文献
33.
Pavel V. Belichenko Rime Madani Lorianne Rey-Bellet Maria Pihlgren Ann Becker Adeline Plassard Stephanie Vuillermot Valérie Giriens Rachel L. Nosheny Alexander M. Kleschevnikov Janice S. Valletta Sara K. S. Bengtsson Gordon R. Linke Michael T. Maloney David T. Hickman Pedro Reis Anne Granet Dorin Mlaki Maria Pilar Lopez-Deber Long Do Nishant Singhal Eliezer Masliah Matthew L. Pearn Andrea Pfeifer Andreas Muhs William C. Mobley 《PloS one》2016,11(3)
In Down syndrome (DS) or trisomy of chromosome 21, the β-amyloid (Aβ) peptide product of the amyloid precursor protein (APP) is present in excess. Evidence points to increased APP gene dose and Aβ as playing a critical role in cognitive difficulties experienced by people with DS. Particularly, Aβ is linked to the late-life emergence of dementia as associated with neuropathological markers of Alzheimer’s disease (AD). At present, no treatment targets Aβ–related pathogenesis in people with DS. Herein we used a vaccine containing the Aβ 1–15 peptide embedded into liposomes together with the adjuvant monophosphoryl lipid A (MPLA). Ts65Dn mice, a model of DS, were immunized with the anti-Aβ vaccine at 5 months of age and were examined for cognitive measures at 8 months of age. The status of basal forebrain cholinergic neurons and brain levels of APP and its proteolytic products were measured. Immunization of Ts65Dn mice resulted in robust anti-Aβ IgG titers, demonstrating the ability of the vaccine to break self-tolerance. The vaccine-induced antibodies reacted with Aβ without detectable binding to either APP or its C-terminal fragments. Vaccination of Ts65Dn mice resulted in a modest, but non-significant reduction in brain Aβ levels relative to vehicle-treated Ts65Dn mice, resulting in similar levels of Aβ as diploid (2N) mice. Importantly, vaccinated Ts65Dn mice showed resolution of memory deficits in the novel object recognition and contextual fear conditioning tests, as well as reduction of cholinergic neuron atrophy. No treatment adverse effects were observed; vaccine did not result in inflammation, cellular infiltration, or hemorrhage. These data are the first to show that an anti-Aβ immunotherapeutic approach may act to target Aβ-related pathology in a mouse model of DS. 相似文献
34.
The nucleotide sequence of a bacteriocin-encoding plasmid isolated from Klebsiella pneumoniae (pKlebB-K17/80) has been determined. The encoded klebicin B protein is similar in sequence to the DNase pyocins and colicins, suggesting that klebicin B functions as a nonspecific endonuclease. The klebicin gene cluster, as well as the plasmid backbone, is a chimera, with regions similar to those of pore-former colicins, nuclease pyocins and colicins as well as noncolicinogenic plasmids. Similarities between pKlebB plasmid maintenance functions and those of the colicin E1 plasmid suggest that pKlebB is a member of the ColE1 plasmid replication family. 相似文献
35.
Pasquinucci L Parenti C Turnaturi R Aricò G Marrazzo A Prezzavento O Ronsisvalle S Georgoussi Z Fourla DD Scoto GM Ronsisvalle G 《Life sciences》2012,90(1-2):66-70
AimsPowerful analgesics relieve pain primarily through activating mu opioid receptor (MOR), but the long-term use of MOR agonists, such as morphine, is limited by the rapid development of tolerance. Recently, it has been observed that simultaneous stimulation of the delta opioid receptor (DOR) and MOR limits the incidence of tolerance induced by MOR agonists. 3-[(2R,6R,11R)-8-hydroxy-6,11-dimethyl-1,4,5,6-tetrahydro-2,6-methano-3-benzazocin-3(2H)-yl]-N-phenylpropanamide (LP1) is a centrally acting agent with antinociceptive activity comparable to morphine and is able to bind and activate MOR and DOR. The aim of this work was to evaluate and compare the induction of tolerance to antinociceptive effects from treatment with LP1 and morphine.Main methodsHere, we evaluated the pharmacological effects of LP1 administered at a dose of 4 mg/kg subcutaneously (s.c.) twice per day for 9 days to male Sprague–Dawley rats. In addition, the LP1 mechanism of action was assessed by measurement of LP1-induced [35S]GTPγS binding to the MOR and DOR.Key findingsData obtained from the radiant heat tail flick test showed that LP1 maintained its antinociceptive profile until the ninth day, while tolerance to morphine (10 mg/kg s.c. twice per day) was observed on day 3. Moreover, LP1 significantly enhanced [35S]GTPγS binding in the membranes of HEK293 cells expressing either the MOR or the DOR.SignificanceLP1 is a novel analgesic agent for chronic pain treatment, and its low tolerance-inducing capability may be correlated with its ability to bind both the MOR and DOR. 相似文献
36.
Moscatiello R Baldan B Squartini A Mariani P Navazio L 《Molecular plant-microbe interactions : MPMI》2012,25(11):1387-1395
Oligogalacturonides are pectic fragments of the plant cell wall, whose signaling role has been described thus far during plant development and plant-pathogen interactions. In the present work, we evaluated the potential involvement of oligogalacturonides in the molecular communications between legumes and rhizobia during the establishment of nitrogen-fixing symbiosis. Oligogalacturonides with a degree of polymerization of 10 to 15 were found to trigger a rapid intracellular production of reactive oxygen species in Rhizobium leguminosarum bv. viciae 3841. Accumulation of H(2)O(2), detected by both 2',7'-dichlorodihydrofluorescein diacetate-based fluorescence and electron-dense deposits of cerium perhydroxides, was transient and did not affect bacterial cell viability, due to the prompt activation of the katG gene encoding a catalase. Calcium measurements carried out in R. leguminosarum transformed with the bioluminescent Ca(2+) reporter aequorin demonstrated the induction of a rapid and remarkable intracellular Ca(2+) increase in response to oligogalacturonides. When applied jointly with naringenin, oligogalacturonides effectively inhibited flavonoid-induced nod gene expression, indicating an antagonistic interplay between oligogalacturonides and inducing flavonoids in the early stages of plant root colonization. The above data suggest a novel role for oligogalacturonides as signaling molecules released in the rhizosphere in the initial rhizobium-legume interaction. 相似文献
37.
Increased App expression in a mouse model of Down's syndrome disrupts NGF transport and causes cholinergic neuron degeneration 总被引:15,自引:0,他引:15
Salehi A Delcroix JD Belichenko PV Zhan K Wu C Valletta JS Takimoto-Kimura R Kleschevnikov AM Sambamurti K Chung PP Xia W Villar A Campbell WA Kulnane LS Nixon RA Lamb BT Epstein CJ Stokin GB Goldstein LS Mobley WC 《Neuron》2006,51(1):29-42
Degeneration of basal forebrain cholinergic neurons (BFCNs) contributes to cognitive dysfunction in Alzheimer's disease (AD) and Down's syndrome (DS). We used Ts65Dn and Ts1Cje mouse models of DS to show that the increased dose of the amyloid precursor protein gene, App, acts to markedly decrease NGF retrograde transport and cause degeneration of BFCNs. NGF transport was also decreased in mice expressing wild-type human APP or a familial AD-linked mutant APP; while significant, the decreases were less marked and there was no evident degeneration of BFCNs. Because of evidence suggesting that the NGF transport defect was intra-axonal, we explored within cholinergic axons the status of early endosomes (EEs). NGF-containing EEs were enlarged in Ts65Dn mice and their App content was increased. Our study thus provides evidence for a pathogenic mechanism for DS in which increased expression of App, in the context of trisomy, causes abnormal transport of NGF and cholinergic neurodegeneration. 相似文献
38.
Jeffrey Kennedy Hitoshi Katsuta Min-Ho Jung Lorella Marselli Allison B. Goldfine Ulysses J. Balis Dennis Sgroi Susan Bonner-Weir Gordon C. Weir 《PloS one》2010,5(6)
Background
There is great interest about the possible contribution of ER stress to the apoptosis of pancreatic beta cells in the diabetic state and with islet transplantation.Methods and Findings
Expression of genes involved in ER stress were examined in beta cell enriched tissue obtained with laser capture microdissection (LCM) from frozen sections of pancreases obtained from non-diabetic subjects at surgery and from human islets transplanted into ICR-SCID mice for 4 wk. Because mice have higher glucose levels than humans, the transplanted beta cells were exposed to mild hyperglycemia and the abnormal environment of the transplant site. RNA was extracted from the LCM specimens, amplified and then subjected to microarray analysis. The transplanted beta cells showed an unfolded protein response (UPR). There was activation of many genes of the IRE-1 pathway that provide protection against the deleterious effects of ER stress, increased expression of ER chaperones and ERAD (ER-associated protein degradation) proteins. The other two arms of ER stress, PERK and ATF-6, had many down regulated genes. Downregulation of EIF2A could protect by inhibiting protein synthesis. Two genes known to contribute to apoptosis, CHOP and JNK, were downregulated.Conclusions
Human beta cells in a transplant site had UPR changes in gene expression that protect against the proapoptotic effects of unfolded proteins. 相似文献39.
Novel monodisperse PEG-dendrons as new tools for targeted drug delivery: synthesis, characterization and cellular uptake 总被引:2,自引:0,他引:2
Berna M Dalzoppo D Pasut G Manunta M Izzo L Jones AT Duncan R Veronese FM 《Biomacromolecules》2006,7(1):146-153
Dendrimers, dendrons, and hyperbranched polymers are gaining popularity as novel drugs, imaging agents, and drug delivery systems. They present advantages of well-defined molecular weight, multivalent surfaces, and high drug carrying capacity. Moreover, it is emerging that such architectures can display unique endocytic properties. As poly(ethylene glycol) (PEG) is widely used for protein and drug conjugation, the aim of this study was for the first time to synthesize novel, branched PEG-based architectures, to define their cytotoxicity and, via preparation of Oregon green (OG) conjugates define the effect of structure on their cellular uptake. Five PEG-based dendrons were synthesized using monodisperse Fmoc-amino PEG propionic acid (M(w) = 840) as a monomer, and cadaverine, tris(2-aminoethyl)amine or lysine as the branching moieties. These were diamino,bisPEG (M(w) = 1300); triamino,trisPEG (Mw = 1946); tetraamino,tetraPEG (M(w) = 3956); monocarboxy,diamino,bisPEG (M(w) = 1346); and monocarboxy,tetraamino,tetraPEG (M(w) = 3999). These products had NH(2) or both NH(2) and COOH terminal groups and the identity was verified by amino group analysis and ESI-TOF mass spectroscopy. Purity was determined by HPLC. Representative structures were not toxic towards an endothelial-like cell line (ECV304) at concentrations up to 4 mg/mL (over 72 h). At 37 degrees C, all of the OG-labeled PEG dendrons showed progressive uptake by ECV304 cells, but tetraamino,tetraPEG showed the greatest rate of internalization over the first 20 min. Cellular uptake was inhibited at 4 degrees C, and PEG dendron localization to perinuclear vesicles was confirmed by fluorescence microscopy. These well-defined novel architectures have potential for further development as targetable drug delivery systems or tools for construction of structurally defined modified surfaces. 相似文献
40.
The mortality disadvantage of African Americans is well documented, but previous studies have not considered its implications for population theory in the general case of industrialized nation states with high levels of income inequality. This paper examines the relevance of classic epidemiological theory to the extremes of income and mortality observed in Chicago, one of America's most racially divided cities. We analyze cause-specific death rates for black and non-black male populations residing in Chicago's community areas by using linked data from the 1990 Census and from 1989-1991 individual death certificates. The same cause-of-death patterns explain much of the mortality of black and non-black men. These two major structures include one, degenerative diseases, the other, "tough-living" causes (accidents, homicides, and liver disease). Community socioeconomic status is strongly related to tough-living deaths within each racial group, and to degenerative deaths for African Americans. Black men's tough-living mortality is much greater than non-blacks', but their younger age structure suppresses their degenerative death rates. Aggregate unemployment and social disorganization account for the most salient disparities in mortality across racial groups. This patterning of mortality along a socioeconomic continuum supports epidemiological theory and extends its applicability to highly unequal populations within industrialized countries. 相似文献