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81.
Noha Ahmed Nasef Sunali Mehta Penny Powell Gareth Marlow Tom Wileman Lynnette R Ferguson 《PloS one》2015,10(6)
Background
Inflammatory bowel disease (IBD) is a heterogeneous chronic inflammatory disease affecting the gut with limited treatment success for its sufferers. This suggests the need for better understanding of the different subtypes of the disease as well as nutritional interventions to compliment current treatments. In this study we assess the ability of a hydrophilic feijoa fraction (F3) to modulate autophagy a process known to regulate inflammation, via TLR2 using IBD cell lines.Method
Mouse embryonic fibroblasts (MEF) deleted for ATG5, and two intestinal epithelial cells HCT15 and HCT116, were used to test the anti-inflammatory effect of F3 after stimulating the cells with a TLR2 specific ligand PAM3CSK4.Results
F3 was able to reduce TLR2 specific inflammation and stimulate autophagy in MEFs and HCT15 cells but not in HCT116 cells. The anti-inflammatory effect was reduced in the MEF cells deleted for ATG5. In addition, the activation of autophagy by F3 was enhanced by PAM3CSK4.Conclusion
F3 of feijoa can interact with cells via a TLR2 specific mechanism and reduce Nuclear factor kappa B (NF-κB) activation in part due to stimulation of autophagy. These results suggest that there is potential benefit in using feijoa extracts as part of dietary interventions to manage IBD in patients. 相似文献82.
Youssef NH Nguyen T Sabatini DA McInerney MJ 《Journal of industrial microbiology & biotechnology》2007,34(7):497-507
Biosurfactants could potentially replace or be used in conjunction with synthetic surfactants to provide for more cost-effective
subsurface remediation. The design of surfactant formulations that are effective in lowering interfacial tension (IFT), which
is necessary to mobilize entrapped hydrocarbons, requires information about the surface-active agent (surfactant) and the
targeted non-aqueous phase liquids (NAPL). We hypothesized that biosurfactant and synthetic surfactant mixtures can be formulated
to provide the appropriate hydrophobic/hydrophilic conditions necessary to produce low IFT against NAPLs, and that such mixtures
will produce synergism that make them more effective than individual biosurfactants or synthetic surfactants. Our work tested
the interfacial activity of biosurfactants from individual strains and mixtures of biosurfactants from different strains with
and without a synthetic surfactant. Multiple regression analysis showed that, for lipopeptide biosurfactants produced by various
Bacillus species, the interfacial activity against toluene depended on the relative proportions of 3-OH-C14, C15, C16, and C18 in the fatty acid tail. As the fatty acid composition became more heterogeneous the system produced lower IFT against toluene.
In mixtures of lipopeptide biosurfactants with the more hydrophilic, rhamnolipid biosurfactant, the IFT against toluene decreased
as the percentage of the 3-OH C14 fatty acid increased in the lipopeptide. Mixtures of lipopeptide biosurfactants with the more hydrophobic synthetic surfactant,
C12, C13-8PO SO4Na, were able to produce low IFT against hexane and decane. In general, we found that lipopeptide biosurfactants with a heterogeneous
fatty acid composition or mixtures of lipopeptide and rhamnolipid biosurfactants lowered the IFT against hydrophilic NAPLs.
Conversely, mixtures of lipopeptide biosurfactants with a more hydrophobic synthetic surfactant lowered the IFT against hydrophobic
NAPLs. 相似文献
83.
Meningococcal polysaccharides are medically important molecules and are the active components of vaccines against Neisseria meningiditis serogroups A, C, W135, and Y. This study demonstrates that free solution capillary zone electrophoresis (CZE) using simple phosphate/borate separation buffers is capable of separating intact, native polysaccharides from these four serogroups. Separation appeared to be robust with respect to variations in test conditions and behaved in expected ways with respect to changes in temperature, ionic strength, and addition of an organic modifier. Serogroups W135 and Y are composed of sialic acid residues alternating with either galactose or glucose, respectively. Separation of these serogroups could be achieved using phosphate buffer and was therefore not dependent on differential complexation with borate. Addition of sodium dodecyl sulfate to the separation buffer (i.e., MEKC) resulted in peak splitting for all four serogroups. Changes in polysaccharide size did not affect migration time for the size range examined, but serogroup C polysaccharide (a sialic acid homopolymer) was separable from sialic acid monosaccharide. CZE quantification of multiple lots of each of the four serogroups was compared to wet chemical determination by phosphorus or sialic acid measurement. Results from CZE determination showed good agreement with the wet chemical methods. 相似文献
84.
Fluorimetric determination of febuxostat in dosage forms and in real human plasma via Förster resonance energy transfer 下载免费PDF全文
A rapid, simple, selective and precise fluorimetric method was developed and validated for determination of a selective xanthine oxidase inhibitor; febuxostat (FBX) in pharmaceutical formulations and in human plasma. The proposed method is based on quenching effect of FBX on the fluorescence intensity of terbium (Tb3+) through fluorescence resonance energy transfer (FRET) from Tb3+ to FBX. The formed complex was measured at λex. 320 nm/λem. 490 nm against a reagent blank. Fluorescence intensity of Tb3+ was diminished when FBX was added. A linear relationship between the fluorescence quenching value of the formed complex and the concentration of FBX was investigated. The reaction conditions and the fluorescence spectral properties of the complex have been studied. The linearity range of the developed method was 1.0–16.0 μg/ml. The suggested method was applied successfully for the estimation of FBX in bulk powder, dosage forms and spiked plasma samples with excellent recoveries (96.79–98.89%). In addition, the developed method has been successfully applied for determination of FBX in real plasma samples collected from healthy volunteers with good recoveries (82.06–85.65%). All obtained results of the developed method were statistically analyzed and validated according to ICH (International Conference on Harmonization) guidelines. 相似文献
85.
Liraglutide ameliorated peripheral neuropathy in diabetic rats: Involvement of oxidative stress,inflammation and extracellular matrix remodeling 下载免费PDF全文
Passant E. Moustafa Noha F. Abdelkader Sally A. El Awdan Osama A. El‐Shabrawy Hala F. Zaki 《Journal of neurochemistry》2018,146(2):173-185
86.
Sonal Dalvi Noha H. Youssef Babu Z. Fathepure 《Extremophiles : life under extreme conditions》2016,20(3):311-321
A benzoate-degrading archaeal enrichment was developed using sediment samples from Rozel Point at Great Salt Lake, UT. The enrichment degraded benzoate as the sole carbon source at salinity ranging from 2.0 to 5.0 M NaCl with highest rate of degradation observed at 4.0 M. The enrichment was also tested for its ability to grow on other aromatic compounds such as 4-hydroxybenzoic acid (4-HBA), gentisic acid, protocatechuic acid (PCA), catechol, benzene and toluene as the sole sources of carbon and energy. Of these, the culture only utilized 4-HBA as the carbon source. To determine the initial steps in benzoate degradation pathway, a survey of ring-oxidizing and ring-cleaving genes was performed using degenerate PCR primers. Results showed the presence of 4-hydroxybenzoate 3-monooxygenase (4-HBMO) and protocatechuate 3, 4-dioxygenase (3,4-PCA) genes suggesting that the archaeal enrichment might degrade benzoate to 4-HBA that is further converted to PCA by 4-HBMO and, thus, formed PCA would undergo ring-cleavage by 3,4-PCA to form intermediates that enter the Krebs cycle. Small subunit rRNA gene-based diversity survey revealed that the enrichment consisted entirely of class Halobacteria members belonging to the genera Halopenitus, Halosarcina, Natronomonas, Halosimplex, Halorubrum, Salinarchaeum and Haloterrigena. Of these, Halopenitus was the dominant group accounting for almost 91 % of the total sequences suggesting their potential role in degrading oxygenated aromatic compounds at extreme salinity. 相似文献
87.
Effects of a meal replacement system alone or in combination with phentermine on weight loss and food cravings 下载免费PDF全文
88.
89.
Emma C. Chapman Alasdair R. O’Dell Noha M. Meligi Daniel R. Parsons 《Chronobiology international》2017,34(9):1300-1314
Environmental cues allow organisms to synchronise their internal biological rhythms with external environmental cycles. These rhythms are regulated on a molecular level by oscillating interactions between clock genes and their proteins. Light is a particularly relevant environmental cue, provisioning daily information via light/dark cycles as well as seasonal information via day-length (photoperiod). Despite the ecological and commercial importance of bivalves, little is known about the interactions comprising their molecular clock mechanism. This study investigates the link between the annual seasonal progression and reproductive development in the blue mussel (Mytilus edulis), using mRNA expression patterns of clock-associated genes: Clock, Cry1¸ ARNT, Timeout-like, ROR/HR3 and aaNAT, in the gonads of both sexes, sampled over three daily time-points on a tidal beach during the winter and summer solstices. Significant differences in mRNA expression levels, including some seasonal differences at comparable time-points, were detected for all genes with the exception of Timeout-like. These differences occurred seasonally within sex (Clock, Cry1, ROR/HR3), seasonally between sexes (Clock, Cry1, ARNT, ROR/HR3, aaNAT) and daily between sexes (Cry1), although no significant daily differences were detected in summer or winter for either sex for any of the genes. This study reveals that clock-associated genes show seasonal responses in this species of bivalve. Understanding the mechanisms by which environmental cues drive biological rhythms is critical to understanding the seasonal sensitivity of this keystone species to environmental changes. 相似文献
90.
Noha H. Youssef Ibrahim F. Farag Christian Rinke Steven J. Hallam Tanja Woyke Mostafa S. Elshahed 《PloS one》2015,10(6)
The “Latescibacteria” (formerly WS3), member of the Fibrobacteres–Chlorobi–Bacteroidetes (FCB) superphylum, represents a ubiquitous candidate phylum found in terrestrial, aquatic, and marine ecosystems. Recently, single-cell amplified genomes (SAGs) representing the “Latescibacteria” were obtained from the anoxic monimolimnion layers of Sakinaw Lake (British Columbia, Canada), and anoxic sediments of a coastal lagoon (Etoliko lagoon, Western Greece). Here, we present a detailed in-silico analysis of the four SAGs to gain some insights on their metabolic potential and apparent ecological roles. Metabolic reconstruction suggests an anaerobic fermentative mode of metabolism, as well as the capability to degrade multiple polysaccharides and glycoproteins that represent integral components of green (Charophyta and Chlorophyta) and brown (Phaeophycaea) algae cell walls (pectin, alginate, ulvan, fucan, hydroxyproline-rich glycoproteins), storage molecules (starch and trehalose), and extracellular polymeric substances (EPSs). The analyzed SAGs also encode dedicated transporters for the uptake of produced sugars and amino acids/oligopeptides, as well as an extensive machinery for the catabolism of all transported sugars, including the production of a bacterial microcompartment (BMC) to sequester propionaldehyde, a toxic intermediate produced during fucose and rhamnose metabolism. Finally, genes for the formation of gas vesicles, flagella, type IV pili, and oxidative stress response were found, features that could aid in cellular association with algal detritus. Collectively, these results indicate that the analyzed “Latescibacteria” mediate the turnover of multiple complex organic polymers of algal origin that reach deeper anoxic/microoxic habitats in lakes and lagoons. The implications of such process on our understanding of niche specialization in microbial communities mediating organic carbon turnover in stratified water bodies are discussed. 相似文献