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91.
Conjugated isomers of linoleic acid have beneficial effects on human health, with demonstrated anticarcinogenic, antiatherogenic, antioxidant, and anti‐inflammatory properties. Previous studies have shown that the loss of sex hormones induced by orchidectomy affects vascular function and serum lipids. The objective of this work is to evaluate the effect of conjugated linoleic acid (CLA) on serum lipids, cardiac, renal, and hepatic markers in orchidectomized Sprague‐Dawley rats. Male sex hormone deprivation is induced by orchidectomy to 24‐week‐old rats. The rats are fed a diet containing 1.8% w/w CLA, or a control diet for 8 weeks. At the end of the treatment, serum markers are measured using commercially available kits. The concentrations found in the orchidectomized‐CLA (ORX‐CLA) group of total cholesterol, low‐density lipoproteins (LDL), as well as the atherogenic index, concentrations of creatine kinase, lactate dehydrogenase, C‐reactive protein, glucose, urea, uric acid, creatinine, albumin, calcium, total protein, and bilirubin are significantly lower compared to the orchidectomized‐control (ORX‐C) group. The concentrations of high‐density lipoproteins (HDL), calcium, total protein, albumin, total bilirubin, and indirect bilirubin are significantly higher in the ORX‐CLA group than in the ORX‐C group. The CLA‐supplemented diet exerts a beneficial effect on different biochemical parameters negatively affected by orchidectomy, which may result in vascular protection. Practical Applications: The relationship between testosterone deficiency and the alteration of serum lipids is demonstrated; however, it is demonstrated in this study that the markers of renal damage, cardiac damage, and oxidative stress are also negatively affected by the lack of this hormone. This information has enriched the understanding about the relationship between testosterone deficiency and the development of different diseases such as metabolic syndrome, type 2 diabetes, kidney failure, osteoporosis, cardiovascular diseases, and cancer. On the other hand, CLA has been studied mainly as a nutraceutical and sports supplement; the information in this study will help to expand the knowledge about the benefits of these isomers of linoleic acid, providing guidelines for its use as a protection against negative effects triggered by orchidectomy.  相似文献   
92.
Pyridine Nucleotide-Disulfide Oxidoreductase Domain 2 (PYROXD2; previously called YueF) is a mitochondrial inner membrane/matrix-residing protein and is reported to regulate mitochondrial function. The clinical importance of PYROXD2 has been unclear, and little is known of the protein’s precise biological function. In the present paper, we report biallelic variants in PYROXD2 identified by genome sequencing in a patient with suspected mitochondrial disease. The child presented with acute neurological deterioration, unresponsive episodes, and extreme metabolic acidosis, and received rapid genomic testing. He died shortly after. Magnetic resonance imaging (MRI) brain imaging showed changes resembling Leigh syndrome, one of the more common childhood mitochondrial neurological diseases. Functional studies in patient fibroblasts showed a heightened sensitivity to mitochondrial metabolic stress and increased mitochondrial superoxide levels. Quantitative proteomic analysis demonstrated decreased levels of subunits of the mitochondrial respiratory chain complex I, and both the small and large subunits of the mitochondrial ribosome, suggesting a mitoribosomal defect. Our findings support the critical role of PYROXD2 in human cells, and suggest that the biallelic PYROXD2 variants are associated with mitochondrial dysfunction, and can plausibly explain the child’s clinical presentation.  相似文献   
93.
The polar fraction of virgin olive oil was separated into two main parts (A and B) using solid phase extraction. Analysis of individual components by RP-HPLC indicated that the part (A) contained only simple phenols and phenolic acids. Part (B) had a complex nature. The two parts tested for their antioxidant activity showed relatively high protection factors in safflower oil stored at 80°C. Part B was found to contribute more than part A to the stability of the oil. The antioxidant activity of both fractions was related to their content of total polyphenols and o-diphenols. Acidic and alkaline hydrolysis showed significant quantitative changes in the HPLC profiles indicating the presence of ether and ester bonds while high-performance anion exchange chromatography of sugars after hydrolysis gave evidence for the presence of only traces of glycosides. A first attempt to identify a characteristic chromatographic peak of part B by HPLC fractionation and mass spectrometry showed the presence of an ester of tyrosol most probably with a dicarboxylic acid. © 1997 SCI.  相似文献   
94.
The copolymerization of acrylonitrile with maleic anhydride was investigated to synthesize acylic reactive polymers for manufacture of membranes that serve as support for covalent enzyme immobilization. The free-radical copolymer synthesis was carried out in solution (N,N-dimethylformamide (DMF), dimethylacetamide (DMAC), γ-butyrolactone, ethylene carbonate), by precipitation polymerization (dioxane) as well as bulk polymerization. The polymers were characterized using IR spectroscopy, elementary analysis, NMR spectroscopy, gel permeation chromatography, viscosity measurements, osmometry and potentiometry. The kinetic parameters were followed by dilatometric measurements up to high conversions. The anhydride content in the monomer mixtures showed a significant influence on the rate of polymerization and the molecular weight. With raised concentration of anhydride the polymerization rate and molecular weights decreased. Film forming polymers (M̄η > 30 000 g/mol) can be obtained by all copolymerization procedures with exception of solution polymerization in DMF and DMAC, respectively. The content of maleic anhydride in the membrane polymers did not exceed 5 mol-%, even though the maleic anhydride content in the monomer mixtures was raised up to the equimolar mixture. Nevertheless, such low maleic anhydride content of prepared membranes is enough for successful enzyme immobilization with amyloglucosidase (copolymer was prepared in γ-butyrolactone, M̄η = 49 000 g/mol, c = 0,3 mol-%).  相似文献   
95.
Margot Baird 《纺织学会志》2013,104(1):156-162
It is shown that the expansion of lightweight worsted fabrics measured under autoclave conditions is greater than that measured under atmospheric conditions at equivalent levels of moisture regain. It is also shown that the moisture regain of the fabric at intermediate pressures appears to be independent of the maximum pressure which the autoclave attains.  相似文献   
96.
There are potential nutritional and sensory benefits of adding sauces to hospital meals. The aim of this study was to develop nutrient fortified sauces with acceptable sensory properties suitable for older people at risk of undernutrition. Tomato, gravy, and white sauce were fortified with macro‐ and micronutrients using food ingredients rich in energy and protein as well as vitamin and mineral premixes. Sensory profile was assessed by a trained panel. Hedonic liking of fortified compared with standard sauces was evaluated by healthy older volunteers. The fortified sauces had higher nutritional value than the conventional ones, for example the energy content of the fortified tomato, white sauce, and gravy formulations were increased between 2.5‐ and 4‐fold compared to their control formulations. Healthy older consumers preferred the fortified tomato sauce compared with unfortified. There were no significant differences in liking between the fortified and standard option for gravy. There were limitations in the extent of fortification with protein, potassium, and magnesium, as excessive inclusion resulted in bitterness, undesired flavors, or textural issues. This was particularly marked in the white sauce to the extent that their sensory characteristics were not sufficiently optimized for hedonic testing. It is proposed that the development of fortified sauces is a simple approach to improving energy intake for hospitalized older people, both through the nutrient composition of the sauce itself and due to the benefits of increasing sensorial taste and lubrication in the mouth.  相似文献   
97.
The cytoprotective effects of five flavonoids (quercetin, rutin, catechin, kaempferol and morin) and four hydroxycinnamic acids (caffeic, ferulic, sinapic and chlorogenic acids) were evaluated by the degree of protection they provided against H2O2-induced damage to human neuroblastoma SH-SY5Y cells. All compounds exhibited protection against H2O2-mediated cytotoxicity in a dose dependent manner. The concentration required to give a 50% reduction in cell death (EC50 value) were derived from their dose–response relationships. The cytoprotective activities of these phenolic compounds in the order of quercetin > caffeic acid > rutin > chlorogenic acid > catechin > ferulic acid > sinapic acid > morin > kaempferol. The EC50 values of the phenolic compounds were strongly related to their chemical structures. The EC50 values were compared with the antioxidant activities as determined by five different chemically based antioxidant assays [2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP) and lipid peroxidation inhibition capacity (LPIC)]. The ability of these phenolic compounds to protect from H2O2-induced SH-SY5Y cell death correlated (r 2 = 0.85) with their determined LPIC values and weakly (r 2 = 0.44) with their ABTS activities. There was no correlation between EC50 values and ORAC, FRAP or DPPH activities. The cytoprotection assay is a more biologically relevant measurement than the chemically defined antioxidant activity assays because it uses human cells as a substrate and therefore accounts for some aspects of uptake, metabolism and location of antioxidant compounds within cells.  相似文献   
98.
99.
In mercury adsorption on activated carbons both physisorptive and chemisorptive mechanisms play a role. The systematic investigation of Hg0 chemisorption is difficult because equilibrium capacities cannot be determined due to slow adsorption mechanisms. Therefore, the present publication suggests a three‐step approach: 1) Breakthrough curves are used to assess the dynamics of Hg0 adsorption. 2) The contributions of physisorption and chemisorption can be distinguished by coupled adsorption and desorption experiments. 3) Temperature programmed desorption (TPD) experiments are performed to get information about specific chemisorptive binding sites on the surface. This approach was tested on four characteristic examples of impregnated and non‐impregnated activated carbons.  相似文献   
100.
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