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1.

Background

The purpose of this investigation was to determine the effects of a dietary supplement (Ambrotose AO®) on resting and exercise-induced blood antioxidant capacity and oxidative stress in exercise-trained and untrained men and women.

Methods

25 individuals (7 trained and 5 untrained men; 7 trained and 6 untrained women) received Ambrotose AO® (4 capsules per day = 2 grams per day) or a placebo for 3 weeks in a random order, double blind cross-over design (with a 3 week washout period). Blood samples were collected at rest, and at 0 and 30 minutes following a graded exercise treadmill test (GXT) performed to exhaustion, both before and after each 3 week supplementation period. Samples were analyzed for Trolox Equivalent Antioxidant Capacity (TEAC), Oxygen Radical Absorbance Capacity (ORAC), malondialdehyde (MDA), hydrogen peroxide (H2O2), and nitrate/nitrite (NOx). Quality of life was assessed using the SF-12 form and exercise time to exhaustion was recorded. Resting blood samples were analyzed for complete blood count (CBC), metabolic panel, and lipid panel before and after each 3 week supplementation period. Dietary intake during the week before each exercise test was recorded.

Results

No condition effects were noted for SF-12 data, for GXT time to exhaustion, or for any variable within the CBC, metabolic panel, or lipid panel (p > 0.05). Treatment with Ambrotose AO® resulted in an increase in resting levels of TEAC (p = 0.02) and ORAC (p < 0.0001). No significant change was noted in resting levels of MDA, H2O2, or NOx (p > 0.05). Exercise resulted in an acute increase in TEAC, MDA, and H2O2 (p < 0.05), all which were higher at 0 minutes post exercise compared to pre exercise (p < 0.05). No condition effects were noted for exercise related data (p > 0.05), with the exception of ORAC (p = 0.0005) which was greater at 30 minutes post exercise for Ambrotose AO® compared to placebo.

Conclusion

Ambrotose AO® at a daily dosage of 4 capsules per day increases resting blood antioxidant capacity and may enhance post exercise antioxidant capacity. However, no statistically detected difference is observed in resting or exercise-induced oxidative stress biomarkers, in quality of life, or in GXT time to exhaustion.
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2.
Corrosion of the three carbon black materials which differ in their textural, sub-structural, and morphological characteristics is studied in H2SO4 electrolyte at 80 °C at positive polarization. Impregnation of carbon blacks with Nafion® ionomer is found to strongly affect their susceptibility to corrosion, which varies non-monotonically as a function of the Nafion® loading. Low temperature nitrogen adsorption is applied to study the distribution of the ionomer molecules in the carbon matrix.  相似文献   

3.
The effect of cysteine (RSH), methionine (CH3SR), cystine (RSSR) and N-acetylcysteine (ACC) on the corrosion behavior of mild steel in 40% H3PO4 solution without and with Cl, F, Fe3‰+ and their ternary mixture was studied using both potentiostatic and electrochemical impedance (EIS) techniques under anodic and cathodic polarization conditions. The inorganic additives stimulate the overall corrosion reaction while the amino acids inhibit it with a predominant effect on the dissolution of iron. Both RSH and ACC are adsorbed according to Temkin’s isotherm while adsorption of RSSR and CH3SR follows Frumkin and Langmuir isotherms respectively. The standard free energy of adsorption (ΔG ) was found to be in the order: RSSR > RSH ≅ ACC > CH3SR. The binary mixtures of Cl or F with RSH or CH3SR are the best inhibitors (IE > 90%) while those containing ferric ions or blend I and amino acids are not good corrosion inhibitors. EIS measurements showed that the cathodic reaction, hydrogen evolution, is charge transfer controlled while the anodic one, iron dissolution, is a complex process.  相似文献   

4.
The single-crystals of Ca2+, K+-exchanged zeolite Y, and Ca2+, Rb+-exchanged zeolite Y were prepared by using flow method with mixed ion-exchange solution, whose Ca(NO3)2:KNO3 mole ratios were 1:1 (crystal 1) and 1:100 (crystal 2), and Ca(NO3)2:RbNO3 mole ratios were 1:1 (crystal 3) and 1:100 (crystal 4), respectively, with a total concentration of 0.05 M. They were fully dehydrated by vacuum dehydration at 723 K and 1 × 10?6 Torr for 2 days. Their crystals were determined by single-crystal synchrotron X-ray diffraction techniques in the cubic space group \(Fd \overline{3}\) m, respectively, and were refined to the final error indices R 1/wR 2 = 0.057/0.196, 0.073/0.223, 0.055/0.188, and 0.049/0.175 for crystals 1, 2, 3, and 4, respectively. In the structure of crystal 1 (|Ca23K29|[Si117Al75O384]-FAU), 23 Ca2+ ions per unit cell occupy sites I, II′, and II; 29 K+ ions per unit cell are at sites II′, II, and III′. In the structure of crystal 2 (|Ca18.5K38|[Si117Al75O384]-FAU), 18.5 Ca2+ ions per unit cell occupy sites I, I′, and II; 38 K+ ions are at sites I′, II, and III′. In the structure of crystal 3 (|Ca27Rb21|[Si117Al75O384]-FAU), 27 Ca2+ ions per unit cell occupy sites I, II′, and II; 21 Rb+ ions per unit cell are at sites II′, II, and III. In the structure of crystal 4 (|Ca18Rb39|[Si117Al75O384]-FAU), 18 Ca2+ ions per unit cell occupy sites I and II; 39 Rb+ ions per unit cell are at sites I′, II′, II, III, and III′. In the four crystals, the Ca2+ ion which has much smaller size and higher charge than other cations such as K+ and Rb+ energetically preferred at site I and so the first to be filled on it. Unlike Ca2+ ion, no K+ and Rb+ ions are found at site I, which are clearly less favorable for K+ and Rb+ ions.  相似文献   

5.

Background  

Probiotics purportedly reduce symptoms of gastrointestinal and upper respiratory-tract illness by modulating commensal microflora. Preventing and reducing symptoms of respiratory and gastrointestinal illness are the primary reason that dietary supplementation with probiotics are becoming increasingly popular with healthy active individuals. There is a paucity of data regarding the effectiveness of probiotics in this cohort. The aim of this study was to evaluate the effectiveness of a probiotic on faecal microbiology, self-reported illness symptoms and immunity in healthy well trained individuals.  相似文献   

6.
The effect of supplementing 200 mg/kg body weight palm vitamin E (PVE) and 200 mg/kg body weight α-tocopherol (α-loc) on the healing of wounds in streptozotocin-induced diabetic rats was evaluated. The antioxidant potencies of these two preparations of vitamin E were also evaluated by determining the antioxidant enzyme activities, namely, glutathione peroxidase (GPx) and superoxide dismutase (SOD), and malondialdehyde (MDA) levels in the healing of dermal wounds. Healing was evaluated by measuring wound contractions and protein contents in the healing wounds. Cellular redistribution and collagen deposition were assessed morphologically using cross-sections of paraffin-embedded day-10 wounds stained according to the Van Gieson method. GPx and SOD activities as well as MDA levels were determined in homogenates of day-10 dermal wounds. Results showed that PVE had a greater potency to enhance wound repair and induce the increase in free radical-scavenging enzyme activities than α-Toc. Both PVE and α-Toc, however, were potent antioxidants and significantly reduced the lipid peroxidation levels in the wounds as measured by the reduction in MDA levels.  相似文献   

7.
Visualization of infrared radiation of Tm:YLF-laser at the wavelength of 1908 nm has been investigated in the glass and ceramics samples with compositions of 53ZrF4 · 20 BaF2 · 1HoF3 · 3YbF3 · 3AlF3 · 20NaF and 53ZrF4 · 20BaF2 · 3LaF3 · 1HoF3 · 3AlF3 · 20NaF (mol %). In luminescence spectra of ZBLAN samples doped with Но3+, the bands at the wavelengths of 480, 540, and 650 nm were observed, which correspond to 5 F 35 I 8, 5 S 2, 5 F 45 I 8, and 5 F 55 I 8 electron transitions in Но3+ ions with the maximum intensity of the red band (650 nm). Occupancy of the 5 S 2 and 5 F 4 levels in the ZBLAN: 1% Но3+ samples is related to the sequential absorption of the exciting radiation quanta. The level of 5 F 5 is filled mainly due to the ionic interaction. Additional doping with the Yb3+ ions led to the change of the luminescence color to green and a decrease in the threshold radiation power density of the Tm:YLF-laser in ceramic samples up to 2 W/cm2.  相似文献   

8.
Harmon SD  Kaduce TL  Manuel TD  Spector AA 《Lipids》2003,38(4):469-476
The objective of this study was to determine the effect of 2,2-diphenyl-5-(4-{[(1E)-pyridin-3-yl-methylidene]-amino}piperazin-1-yl)pentanenitrile (SC-26196), a Δ6-desaturase inhibitor, on PUFA metabolism in human cells. SC-26196 inhibited the desaturation of 2 μM [1-14C] 18∶2n−6 by 87–95% in cultured human skin fibroblasts, coronary artery smooth muscle cells, and astrocytes. By contrast, SC-26196 did not affect the conversion of [1-14C]20∶3n−6 to 20∶4 in the fibroblasts, demonstrating that it is selective for Δ6-desaturase. The IC50 values for inhibition of the desaturation of 2 μM [1-14C] 18∶3n−3 and [3-14C]24∶5n−3 in the fibroblasts, 0.2–0.4 μM, were similar to those for the inhibition of [1-14C] 18∶2n−6 desaturation, and the rates of recovery of [1-14C] 18∶2n−6 and [3-14C] 24∶5n−3 desaturation after removal of SC-26196 from the culture medium also were similar. SC-26196 reduced the conversion of [3-14C] 22∶5n−3 and [3-14C] 24∶5n−3 to DHA by 75 and 84%, respectively, but it had no effect on the retroconversion of [3-14C] 24∶6n−3 to DHA. These results demonstrate that SC-26196 effectively inhibits the desaturation of 18- and 24-carbon PUFA and, therefore, decreases the synthesis of arachidonic acid, EPA, and DHA in human cells. Furthermore, they provide additional evidence that the conversion of 22∶5n−3 to DHA involves Δ6-desaturation.  相似文献   

9.
Formation of carbamates by amino groups of poly(ε-l-lysine) (ε-PL) and cross-linking of ε-PL were studied by using 13C and 15N solid-state NMR. It is a characteristic found in ε-PL cast from basic aqueous solution exposed to the air or gaseous CO2. It is not observed in ε-PL cast from acidic aqueous solution and ε-PL cast from degassed aqueous solution under CO2 free environment. The carboxyl carbon and amide nitrogen appear at 164 ppm in 13C spectrum and 92 ppm in 15N spectrum, respectively, which arise when some amino groups of ε-PL react with gaseous CO2 to make carbamates. In addition to these peaks a peak at 171 ppm appears. We assigned it to amide C=O carbons which can not make intermolecular hydrogen bondings since there exist bulky carbamates groups close to these C=O groups. Self-assembly of ionic pairs of ammonium groups and carbamate anions leads to cross-linking of ε-PL.  相似文献   

10.
Atorvastatin calcium (AC) is a second-generation 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor approved for clinical use as a lipid lowering agent. AC, the world's best selling drug is associated with poor oral bioavailability and serious adverse effects like rhabdomyolysis on chronic administration. A biodegradable nanoparticulate approach was introduced here with a view to improving the efficacy and safety of AC. Poly lactide-co-glycolic acid (PLGA) nanoparticles containing atorvastatin calcium were prepared using two stabilizers i.e. didodecyl dimethyl ammonium bromide (DMAB) and Vitamin E tocopheryl polyethylene glycol 1000 succinate (Vit E-TPGS) using a co-solvent approach by emulsion-diffusion-evaporation method. AC loaded PLGA nanoparticles prepared using DMAB and Vit E-TPGS were found to be 120.0 +/- 4.2 nm and 140.0 +/- 1.5 nm (z-average) in size respectively. In vitro release studies at pH 7.4 revealed a zero order release profile for nanoparticles. Efficacy and safety parameters of the prepared nanoparticles against marketed formulation were evaluated in high fat diet fed (hyperlipidemic) rats. It was found that atorvastatin calcium nanoparticles were equally effective in comparison to Lipicure, at a 66%-reduced dose in treating the hyperlipidemia characterized by alterations in PTC, LDL-C, VLDL-C, HDL-C, PTG and PGL in the high fat diet fed rats. On the other hand, when evaluated for safety, nanoparticulate formulation showed no/negligible myotoxicity characterized by lower PC, BUN, CK, LDH and AST levels in comparison to the marketed formulation.  相似文献   

11.
12.
Reduction of NO by NH3 over metal-promoted zeolites represents the principal reaction in the selective catalytic reduction (SCR) technology for NOx removal from Diesel engine exhausts. It has been established that addition of ammonium nitrate (AN) to the reaction mixture substantially enhances the rate of this reaction, decreasing the temperature necessary for an efficient deNOx process. Nevertheless, the nature of this effect has not been completely elucidated. To investigate the NO?+?AN reaction mechanism, we have used individual reactants labeled with either 15N or 18O (or both isotopes), thus obtaining an experimental background for proposing the route of the SCR accelerated by AN addition. For this study, we have used as the catalysts H-BEA and Fe/H-BEA zeolites with various Si/Al ratios and various amounts and states of the iron species.  相似文献   

13.
A novel MoV–YbIII bimetallic chain, {[YbIII(bpy)2(DMF)(H2O)][MoV(CN)8]·0.5bpy·4.5H2O}n (1) (DMF = N,N′-dimethylformamide; bpy = 2,2′-bipyridine), has been constructed by the reaction of [Mo(CN)8]3− with Yb3+ and 2,2′-bipyridine. Complex 1 is confirmed as a host–guest supramolecular structure by X-ray structural analysis. The neighboring chains interact with each other with two types of hydrogen bonds and two types of π···π interactions. Thus complex 1 has a unique 3D network. Magnetic analysis of 1 indicates the presence of a strong YbIII single-ion effect owing to spin–orbital coupling within this system.  相似文献   

14.
15.
16.

Background

Intra-articular hyaluronic acid represents a substantive addition to the therapeutic armamentarium in knee osteoarthritis. We examined the effect of dietary supplementation with a natural extract of chicken combs with a high content of hyaluronic acid (60%) (Hyal-Joint®) (active test product, AP) on pain and quality of life in subjects with osteoarthritis of the knee.

Methods

Twenty subjects aged ≥40 years with knee osteoarthritis (pain for at least 15 days in the previous month, symptoms present for ≥6 months, Kellgren/Lawrence score ≥2) participated in a randomized double-blind controlled trial. Ten subjects received AP (80 mg/day) and 10 placebo for 8 weeks. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and quality of life by the Short Form-36 (SF-36v2) were administered at baseline and after 4 and 8 weeks of treatment.

Results

WOMAC pain (primary efficacy variable) was similar in both study groups (mean [SD]) with 6.6 (4.0) points in the AP group and 6.4 (2.7) in the placebo group (P = 0.943). As compared with baseline, subjects in both groups showed statistically significant improvements in WOMAC pain, stiffness, physical function subscales, and in the aggregate score, but the magnitude of changes was higher in the AP group for WOMAC physical function (-13.1 [12.0] vs. -10.1 [8.6], P = 0.575) and total symptoms (-18.6 [16.8] vs. -15.8 [11.4], P = 0.694). At 4 weeks, statistically significant mean changes compared with baseline were observed in the SF-36v2 scales of role-physical, bodily pain, social functioning and role-emotional among subjects in the AP group, and in physical functioning, bodily pain, and social functioning in the placebo group. At 8 weeks, changes were significant for role-physical, bodily pain, and physical component summary in the AP group, and for physical functioning and role-emotional in the placebo arm. Changes in bodily pain and social functioning were of greater magnitude in subjects given AP.

Conclusion

This pilot clinical trial showed that daily supplementation with oral hyaluronic acid from a natural extract of chicken combs (Hyal-Joint®) was useful to enhance several markers of quality of life in adults with osteoarthritis of the knee. The results warrant further study in larger sample sizes.
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17.
In the present work, methods based on Gas Chromatography (GC), Gas Chromatography–Mass Spectrometry (GC–MS) and 1H-NMR techniques was developed for the characterization and estimation of Polyunsaturated Fatty Esters (PUFA) in biodiesel. The GC method enables the separation, identification and estimation of these polyunsaturated fatty acid methyl esters to be carried out using a highly polar capillary column (100% cyanopropyl silicon). GC–MS was utilized for unambiguous identification and estimation of esters and isomers present in biodiesel. The estimation of PUFA content is important because PUFA content is a part of the EN 14214 specifications of biodiesel. There is no existing standard method for the estimation of total PUFA content in biodiesel. The developed GC method also quantifies EPA and DHA (C20:5 and C22:6) fatty acid methyl esters which can be used as markers for the estimation of fish oil biodiesel. The presence of EPA and DHA indicates the contamination of fish oil in biodiesel. Further, the 1H-NMR technique has also been employed to identify and estimate PUFA containing ≥3 double bonds. The PUFA content was estimated from the integral intensities of the chemical shift region corresponding to all type of double bonds in the 1H-NMR spectra. Based on the developed method, GC fingerprinting of various biodiesel samples was carried out to estimate a PUFA content as low as 1,000 ppm.  相似文献   

18.

Abstract  

In the present study, the nickel-catalyzed cross coupling of aryl halides with benzyl zinc bromides or dialkyl zinc reagents to create C(sp 2)–C(sp 3) bonds has been explored. As pre-catalyst the well-defined and easy-accessible (bispidine)Ni(NO3)2 complex has been applied. After investigation of different reaction parameters a broad scope of C(sp 2)–C(sp 3) bond formations were feasible under mild reaction conditions.  相似文献   

19.
Zirconium umbite, K2ZrSi3O9·H2O, is a microporous framework ion exchanger whose potential as a carrier for Zn2+ ions in antimicrobial formulations has not yet been investigated. Accordingly, batch Zn2+-exchange kinetics of synthetic zirconium umbite (K-UM) and the subsequent antimicrobial action of the zinc-bearing phase (Zn-UM) against Staphylococcus aureus and Escherichia coli are reported. Nonstoicheiometric over-exchange of Zn2+ for K+ was observed and attributed to hydrolysis and complexation reactions of Zn2+ within the umbite framework. The exchange process, which was described by a simple pseudo-first-order model (k 1 = 2.69 × 10−4 min−1, R 2 = 0.992), did not achieve equilibrium within 120 h at 25 °C, by which time the uptake of zinc was found to be 1.04 mmol g−1. The minimal bactericidal concentrations of Zn-UM for E. coli and S. aureus were found to be >10 g cm3 and <1.0 g cm3, respectively.  相似文献   

20.
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