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1.

Background  

Monolysocardiolipin acyltransferase (MLCL AT) catalyzes the acylation of monolysocardiolipin to cardiolipin in mammalian tissues. We previously reported that cardiac cardiolipin levels, MLCL AT and cardiolipin synthase activities were all elevated in rats made hyperthyroid by thyroxine treatment. In this study, we examined if cardiac mitochondrial MLCL AT activity was dependent upon the biosynthesis and level of cardiolipin in the heart. Rat heart mitochondrial MLCL AT activity was determined under conditions in which the levels of cardiac cardiolipin and cardiolipin synthase activity were either reduced or unaltered using four different disease models in the rat. In addition, these parameters were examined in a murine model of cardiac cell differentiation.  相似文献   

2.

Abstract  

In the work discussed in this paper, cyclic voltammetric results obtained for the interaction of ascorbic acid, β-carotene, and three structurally related flavonoids (quercetin, rutin, and morin) with the anion radical of 1,3-dinitrobenzene were used to determine their antioxidant activity. The extent of the antioxidant–anion radical interactions was measured as the antioxidant activity coefficient. Higher values of this coefficient obtained for the three flavonoids in DMF are indicative of their greater antioxidant activity than ascorbic acid and β-carotene in this solvent. On the basis of cyclic voltammetric responses, a possible mechanism of the reaction of the reduction product of 1,3-dinitrobenzene with the antioxidants is proposed. Hyperchem PM3 quantum mechanical semi-empirical calculations of charges on reactive sites of the antioxidants and the 1,3-dinitrobenzene anion radical were also carried out; the results obtained supported the proposed mechanism of interaction.  相似文献   

3.
In this study, we report the green synthesis of nontoxic, stable, and small size gold nanoparticle by using chitosan/sodium lignosulfonate hydrogel with capping/reducing ability for the synthesis of CS/NaLS/Au NPs. The prepared bio-nanocomposite were characterized by advanced physicochemical techniques like Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray spectroscopy (EDX) and X-ray Diffraction (XRD) study. It has been established that CS/NaLS/Au NPs have a spherical shape with a mean diameter from 20 to 30 nm. Diabetes was induced by administration of 60 mg/kg of streptozotocin (STZ) intraperitoneally in 100 mature male mice and they were randomly divided into 5 groups. The negative control group received normal saline and treatment groups received glibenclamide with dose 0.5 mg/kg and 10 and 40 μg/kg of CS/NaLS/Au NPs through gavage for 50 days. In addition, one group considered as positive control (in treated-diabetic). On the last day, serum levels of samples blood glucose, urea and creatinine were measured. After tissue processing, 5 μm sections of the kidneys were prepared and they were stained by periodic acid Schiff (PAS) and used for stereological analysis. In the antioxidant test, the IC50 of CS/NaLS/Au NPs and BHT against DPPH free radicals were 117 and 86 µg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with CS/NaLS/Au NPs were assessed by MTT assay for 48 h about the cytotoxicity properties on normal (HUVEC) cell line. The increased levels of blood glucose and urea were decreased (p < 0.05) significantly in CS/NaLS/Au NPs-treated groups as compared to the untreated diabetic. The kidney weight, kidney volume (Volume of cortex, medulla, glomerulus, proximal and distal tubules, collecting ducts, loop of Henle, interstitial tissues, and vessels) and kidney structures length (length of proximal and distal tubules, collecting ducts, loop of Henle, and vessels) decreased significantly (p < 0.05) after treatment with high dose of CS/NaLS/Au NPs (p < 0.05). According to the obtained results, CS/NaLS/Au NPs can regulates the levels of blood glucose and urea and inhibits from kidney damages in STZ-induced diabetic mice. This study suggested CS/NaLS/Au NPs as an antidiabetic and nephroprotective drug in the developing countries.  相似文献   

4.

Background  

Noni (Morinda citrifolia) juice has demonstrated antioxidant activity in vitro and in vivo. To evaluate this activity in humans, noni juice from Tahiti (TNJ) was evaluated in a 30 day, double-blind, and placebo controlled clinical trial with 285 current heavy smokers. Research participants were randomly assigned to three daily treatment groups: 118 mL placebo, 29.5 mL TNJ, and 118 mL TNJ. Plasma superoxide anion radicals (SAR) and lipid hydroperoxide (LOOH) levels were measured pre and post-intervention.  相似文献   

5.

Background  

Prickly pear cactus stem (nopal) has been used in folk medicine and a raw material since ancient times. Stems have been proved to possess components with valuable biological activities: anti inflamatory, antioxidant, antiulcerogenic, hypoglycemic, and so forth. Nowadays, people consume foods not only to cover the nutritional requirements, they also demand for healty, natural and convenient foods that show biological activity. This study evaluated the bio-functional effects of consuming tortillas or bars (filled with prickly pear fruit jam) supplemented or not with nopal dietary fiber.  相似文献   

6.
The development of next-generation adsorption, separation, and filtration materials is growing with an increased research focus on polymer composites. In this study, a novel blend of chitosan (CS) and polyethylene oxide (PEO) nanofiber mats was electrospun on titanium (Ti)-coated polyethylene terephthalate (PET) track-etched membranes (TMs) with after-treatment by glutaraldehyde in the vapor phase for enhancing the nanofiber stability by crosslinking. The prepared composite, titanium-coated track-etched nanofiber membrane (TTM-CPnf) was characterized by Fourier transform infra-red (FTIR), water contact angle, and scanning electron microscopy (SEM) analyses. Smooth and uniform CS nanofibers with an average fiber diameter of 156.55 nm were produced from a 70/30 CS/PEO blend solution prepared from 92 wt. % acetic acid and electrospun at 15 cm needle to collector distance with 0.5 mL/h flow rate and an applied voltage of 30 kV on the TTM-CPnf. Short (15 min) and long (72 h)-term solubility tests showed that after 3 h, crosslinked nanofibers were stable in acidic (pH = 3), basic (pH = 13), and neutral (pH = 7) solutions. The crosslinked TTM-CPnf material was biocompatible based on the low mortality of freshwater crustaceans Daphnia magna. The composite membranes comprised of electrospun nanofiber and TMs proved to be biocompatible and may thus be suitable for diverse applications such as dual adsorption–filtration systems in water treatment.  相似文献   

7.

Abstract  

Antioxidant and radical-scavenging properties are alleged to form the basis of the therapeutic properties attributed to the papaya and papaya-based food and drug integrators that have recently appeared on the market. In the present research a biosensor-based method was used to determine the antioxidant capacity of papaya fruit as is, that of several food and drug integrators, and lastly of pure papain alone. Results are compared using a reference spectrofluorimetric method and two other spectrophotometric methods. In addition pro-oxidant properties of the same samples were also checked using two colorimetric methods.  相似文献   

8.
由于脂质过氧化反应(LPO)是导致人体疾病(如肝炎、肝硬化、动脉硬化、脑溢血等)的主要原因, 而黄酮类化合物是一类很强的过氧化反应抑制剂, 因此有必要研究其化学结构与过氧化反应的关系及其抗氧化机理.本文选择α-羟乙基过氧自由基为脂质过氧自由基的模拟物, 采用脉冲辐解方法研究了乙醇溶液中4种典型的黄酮类化合物(槲皮素、芦丁、儿茶素以及黄岑甙)与α-羟乙基过氧自由基的反应动力学, 测得其反应活性顺序为:芦丁>槲皮素>黄岑甙>儿茶素. 同时以黄酮体和邻苯二酚为黄酮类化合物不同结构特征的模型化合物, 用脉冲辐解法测得二者与α-羟乙基过氧自由基的反应速率常数分别为(1.7±0.1)×106和(2.9±0.1)×105 mol-1·dm3·s-1.实验结果表明, 在黄酮类化合物与α-羟乙基过氧自由基的反应中, A环C5位的羟基, C环C2=C3或B-C环的大π键和B环邻二羟基共存时清除α-羟乙基过氧自由基活性最好, 而且C环C2=C3或B-C环大π键的清除活性好于B环邻二羟基, 同时C环是否含有C3-醣甙结构对清除作用没有明显影响. 因此我们推测在黄酮类化合物抑制脂质过氧化反应过程中, 起主要作用的是C环C2=C3或B-C环的大π键与脂质过氧自由基的双键加成反应.  相似文献   

9.
This work is to examine the molecular weight (MW)-anticoagulation activity relationship of sulfated cellulose derivatives (cellulose sulfates, CS). The initial CS with a degree of substitution (1.59) was prepared by homogeneous sulfation of microcrystalline cellulose in an ionic liquid [C4mim]Cl. It was then hydrolyzed in a dilute acidic solution and separated into four MW fractions of 59, 23, 10 × 103 g/mol and below 2.7 × 103 g/mol. The anticoagulation activities based on in vitro assays of coagulation time and coagulation factors in human plasma showed a positive correlation with the MW of CS, while the activity assay of clotting time in rats exhibited a negative correlation with the MW 10–59 × 103 g/mol, and the fraction with a MW <2.7 × 103 g/mol exhibited a more moderate and durable activity. The results indicate that MW is a major factor on the anticoagulant properties of CS derivatives and higher MW range is favorable for in vitro, and lower MW suitable for in vivo applications.  相似文献   

10.

Background  

Numerous popular media sources have developed lists of "Super Foods" and, more recently, "Super Fruits". Such distinctions often are based on the antioxidant capacity and content of naturally occurring compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived from fruits commonly considered "Super Fruits".  相似文献   

11.
Chitosan (CS) is a biopolymer and has reactive amine/hydroxyl groups facilitated its modifications. The purpose of this study is improvement of (CS) physicochemical properties and its capabilities as antiviral and antitumor through modification with 1-(2-oxoindolin-3-ylidene)thiosemicarbazide (3A) or 1-(5-fluoro-2-oxoindolin-3-ylidene)thiosemicarbazide (3B) via crosslinking of poly(ethylene glycol)diglycidylether (PEGDGE) using microwave-assisted as green technique gives (CS-I) and (CS-II) derivatives. However, (CS) derivatives nanoparticles (CS-I NPs) and (CS-II NPs) are synthesized via ionic gelation technique using sodium tripolyphosphate (TPP). Structures of new (CS) derivatives are characterized using different tools. The anticancer, antiviral efficiencies and molecular docking of (CS) and its derivatives are assayed. (CS) derivatives and its nanoparticles show enhancement in cell inhibition toward (HepG-2 and MCF-7) cancer cells in comparison with (CS). (CS-II NPs) reveals the lowest IC50 values are 92.70 ± 2.64 μg/mL and 12.64 µ g/mL against (HepG-2) cell and SARS-CoV-2 (COVID-19) respectively and the best binding affinity toward corona virus protease receptor (PDB ID 6LU7) ?5.71 kcal / mol. Furthermore, (CS-I NPs) shows the lowest cell viability% 14.31 ± 1.48 % and the best binding affinity ?9.98 kcal/moL against (MCF-7) cell and receptor (PDB ID 1Z11) respectively. Results of this study demonstrated that (CS) derivatives and its nanoparticles could be potentially employed for biomedical applications.  相似文献   

12.
Environmental risks, particularly UV radiation, provide a challenge to the function of the skin barrier. Protective measures such as the use of antioxidant products represent a possible method of providing protection to the skin.This paper reports the development of a non-invasive ex vivo method using tape strips of the outermost layers of stratum corneum (SC) from human volunteers in order to determine the effectiveness of an antioxidant emulsion topically applied to prevent lipid peroxidation (LPO) in the horny layer after an UV irradiation exposure. Two different formulations were used: formulation (A), containing Vitamin A, E and C, and formulation (B) containing fish extract. Both formulations were topically applied in vivo on volunteer forearms; then, a tape stripping of the SC of each volunteer was carried out. The lipid peroxidation was measured ex vivo after an UV irradiation of the SC samples. The amount of SC stripped to evaluate differences in lipid peroxidation, the UV irradiation intensity to form lipid peroxides and the accuracy of lipid peroxide analysis were optimized in this methodology using formulation (A). After an exposure application of seven days, a group of three strips of the outermost layers of SC of volunteers was irradiated with an intensity of 182.7 J/cm2 to quantify the LPO inhibition.The percentage of LPO inhibition obtained after topical application of both formulations was in the range of 40–58% demonstrating the effectiveness of the formulations topically applied against lipid peroxidation on human SC. This methodology may be used as a quality control tool to determine ex vivo the percentage of the LPO inhibition on human SC for a variety of antioxidants topically applied.  相似文献   

13.
Candle soot (CS) is a desirable carbon nanomaterial for sensors owing to its highly porous nanostructure and large specific surface area. CS is advantageous in its low-cost and facile preparation compared to graphene and carbon nanotubes, but its pristine nanostructure is susceptible to collapse, hampering its application in electronic devices. This article reports conformal coating of nanoscale crosslinked hydrophilic polymer on CS film using initiated chemical vapor deposition, which well preserved the CS nanostructure and obtained nanoporous CS@polymer composites. Tuning coating thickness enabled composites with different morphologies and specific surface areas. Surprisingly, the humidity sensor made from composite with the lowest filling degree, thus largest specific surface area, showed relatively low sensitivity, which is likely due to its discontinuous structure, thus insufficient conductive channels. Composite sensor with optimum filling degree shows excellent sensing response of more than 103 with the linearity of R2 = 0.9400 within a broad relative humidity range from 11% to 96%. The composite sensor also exhibits outstanding sensing performance compared to literature with low hysteresis (3.00%), a satisfactory response time (28.69 s), and a fast recovery time (0.19 s). The composite sensor is fairly stable and durable even after 24 h soaking in water. Furthermore, embedding a humidity sensor into a face mask realizes real-time monitoring of human breath and cough, suggesting promising applications in respiratory monitoring.  相似文献   

14.
In this study, hydoxyapatite (HA) prepared from calcined bovine bone was studied. Two methods were used for HA sintering: conventional sintering (CS) and microwave sintering (MS). HA was obtained by calcination of bovine bone at 800 °C for 4 h followed by wet ball milling. Afterwards, the powder was compacted under 75 MPa and sintered for 2 h at different temperatures, from 1050 to 1200 °C. It has been found that the bulk density of HA increases by increasing sintering temperature when both CS and MS were used. Nevertheless, at the same temperature and for a shorter time (15 min), the HA sintered by microwave were characterised by a density relatively higher than that of sintered by conventional furnace. For example, at 1100 °C the bulk densities of samples using CS and MS were about 2.49 (for 120 min) and 2.93 (for 15 min) g/cm3, respectively. Furthermore, a near theoretical density (98.6%) was obtained when HA samples were sintered at 1200 °C for 15 min only but using the proposed MS, which was much higher than that (89.7%) of HA samples sintered at the same temperature for longer holding time (120 min). Besides this, the X-ray analyses have shown that heat-treatment, using these two processes, has lead to HA decomposition into tricalcium phosphate and/or tetracalcium phosphate.  相似文献   

15.
Two ferric-ion-based total antioxidant capacity methods: 1,10-phenanthroline (Phen) and ferric reducing antioxidant power (FRAP) were used for determination of antioxidant capacities (AC) of the acetonic and methanolic extracts of vegetable oils. The obtained mean Phen and FRAP values for acetonic extracts of olive oils, rapeseed, rice and four sunflower oils (39.3–336.5 and 39.5–339.6 μmol Fe/100 g) were higher than for methanolic extracts (22.8–307.3 and 23.5–300.1 μmol Fe/100 g). However, antioxidant capacities of methanolic extracts of corn oil, blended oils and two sunflower oils with garden green flowers (56.5–312.9 and 53.9–306.5 μmol Fe/100 g for Phen and FRAP methods, respectively) were higher than for acetonic extracts of these oils (54.2–249.2 and 52.9–244.7 μmol Fe/100 g for Phen and FRAP methods, respectively). There is a linear and significant correlation between these two analytical methods (r = 0.9989 and 0.9986 for acetonic and methanolic extracts). Also, total phenolic compounds (TPC) in the studied oils correlated with their antioxidant capacities determined by Phen and FRAP methods (r = 0.9012, 0.7818 and 0.8947, 0.7830 for acetonic and methanolic extracts, respectively). The comparable precision (R.S.D. = 0.8–4.6%, 0.9–4.9% and 0.7–4.0%, 0.6–4.0% for acetonic and methanolic extracts, respectively) and sensitivity ( = 1.27 × 104, 1.11 × 104 and 2.62 × 104 dm3 mol−1 cm−1) for the proposed Phen and the modified FRAP methods, demonstrate the benefit of the Phen method in the routine analysis of antioxidant capacities of vegetable oils.  相似文献   

16.
Chitosan–poly(vinyl alcohol), CS–PVA, blended membranes were prepared by solution casting of varying proportions of CS and PVA. The blend membranes were then crosslinked interfacially with trimesoyl chloride (TMC)/hexane. The physiochemical properties of the blend membranes were determined using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), tensile test and contact angle measurements. Results from ATR-FTIR show that TMC has crosslinked the blend membranes successfully, and results of XRD and DSC show a corresponding decrease in crystallinity and increase in melting point, respectively. The crosslinked CS–PVA blend membranes also show improved mechanical strength but lower flexibility in tensile testing as compared to uncrosslinked membranes. Contact angle results show that crosslinking has decreased the surface hydrophilicity of the blend membranes. The blend membrane properties, including contact angle, melting point and tensile strength, change with a variation in the blending ratio. They appear to reach a maximum when the CS content is at 75 wt%. In general, the crosslinked blend membranes show excellent stability during the pervaporation (PV) dehydration of ethylene glycol–water mixtures (10–90 wt% EG) at different temperatures (25–70 °C). At 70 °C, for 90 wt% EG in the feed mixture, the crosslinked blend membrane with 75 wt% CS shows the highest total flux of 0.46 kg/(m2 h) and best selectivity of 986. The blending ratio of 75 wt% CS is recommended as the optimized ratio in the preparation of CS–PVA blend membranes for pervaporation dehydration of ethylene glycol.  相似文献   

17.
The cyclopentadienylchromium carbonyl thiocarbonyls Cp2Cr2(CS)2(CO)n (n = 4, 3, 2, 1) have been studied by density functional theory using the B3LYP and BP86 functionals. The lowest energy Cp2Cr2(CS)2(CO)4 structure can be derived from the experimentally characterized unbridged Cp2Cr2(CO)6 structure by replacing the two terminal carbonyl groups furthest from the Cr-Cr bond with two terminal CS groups. The two lowest energy Cp2Cr2(CS)2(CO)3 structures have a single four-electron donor η2-μ-CS group and a formal Cr-Cr single bond of length ∼3.1 Å. In contrast to the carbonyl analogue Cp2Cr2(CO)5 these Cp2Cr2(CS)2(CO)3 structures are viable with respect to disproportionation into Cp2Cr2(CS)2(CO)4 and Cp2Cr2(CS)2(CO)2 and thus are promising synthetic targets. The lowest energy Cp2Cr2(CS)2(CO)2 structures have all two-electron donor CO and CS groups and short CrCr distances around ∼2.3 Å suggesting the formal triple bonds required to give the chromium atoms the favored 18-electron configurations. These Cp2Cr2(CS)2(CO)2 structures are closely related to the known structure for Cp2Cr2(CO)4. In addition, several doubly bridged structures with four-electron donor η2-μ-CS bridges are found for Cp2Cr2(CS)2(CO)2 at higher energies. The global minimum Cp2Cr2(CS)2(CO) structure is a triply bridged triplet with a CrCr triple bond (2.299 Å by BP86). A higher energy singlet Cp2Cr2(CS)2(CO) structure has a shorter Cr-Cr distance of 2.197 Å (BP86) suggesting the formal quadruple bond required to give each chromium atom the favored 18-electron configuration.  相似文献   

18.
Acanthophora spicifera (M.Vahl) Børgesen is a macroalga of great economic importance. This study evaluated the antioxidant responses of two algal populations of A. spicifera adapted to different abiotic conditions when exposed to ultraviolet‐A+ultraviolet‐B radiation (UV‐A+UV‐B). Experiments were performed using the water at two collection points for 7 days of acclimatization and 7 days of exposure to UVR (3 h per day), followed by metabolic analyses. At point 1, water of 30 ± 1 practical salinity unit (psu) had concentrations of 1.06 ± 0.27 mm NH 4 + , 8.47 ± 0.01 mm NO 3 ? , 0.17 ± 0.01 mm PO 4 ? 3 and pH 7.88. At point 2, water of 35 ± 1 psu had concentrations of 1.13 ± 0.05 mm NH 4 + , 3.73 ± 0.01 mm NO 3 ? , 0.52 ± 0.01 mm PO 4 ? 3 and pH 8.55. Chlorophyll a, phycobiliproteins, carotenoids, mycosporins, polyphenolics and antioxidant enzymes (catalase, superoxide dismutase and guaiacol peroxidase) were evaluated. The present study demonstrates that ultraviolet radiation triggers antioxidant activity in the A. spicifera. However, such activation resulted in greater responses in samples of the point 1, with lower salinity and highest concentration of nutrients.  相似文献   

19.
Pooling lauroyl peroxide (LPO) with nitric acid, we used differential scanning calorimetry (DSC) to assess the thermokinetic parameters, such as exothermic onset temperature (T 0), heat of decomposition (ΔH d), frequency factor (A), and the other safety parameters. When LPO was contaminated with nitric acid (HNO3), we found the exploder 1-nitrododecane. Obvious products were sensitive and hazardous chemicals. Concentration reaching 1–12 N HNO3 emitted a large amount of heat. This study combined with curve-fitting method to elucidate its unsafe characteristics and thermally sensitive structure to help prevent runaway reactions, fires and explosions in the process environment. According to the findings and the concept of inherently safer design, LPO runaway reactions could be adequately prevented in the relevant plants.  相似文献   

20.
We synthesized three types of magnetic iron oxide nanoparticles (MNPs), which were meso-2,3-dimercaptosuccinic acid (DMSA) coated MNPs (DMSA@MNPs, 17.3 ± 4.8 nm, negative charge), chitosan (CS) coated MNPs (CS@MNPs, 16.5 ± 6.1 nm, positive charge) and magnetic nanoparticles agglomerates, formed by electronic aggregation between DMSA@MNPs and CS (CS-DMSA@MNPs, 85.7 ± 72.9 nm, positive charge) respectively. The interactions of these MNPs with Oral Squamous Carcinoma Cell KB were investigated. The results showed that cellular uptakes of MNPs were on the dependence of incubation time, nanoparticles concentration and nanoparticles properties such as surface charge, size, etc. The cellular uptake was enhanced with the increase of incubation time and nanoparticles concentration. Although all MNPs could enter to cells, we observed apparent differences in the magnitude of nanoparticles uptaken. The cellular uptake of CS-DMSA@MNPs by KB cells was the highest and that of DMSA@MNPs was the lowest among the three types of MNPs. The same conclusions were drawn via the reduction of water proton relaxation times , resulting from the different iron load of labeled cells using a 1.5 T clinical MR imager. The finding of this study will have implications in the chemical design of nanomaterials for biomedical applications.  相似文献   

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