Search results for "vitamins"
showing 10 items of 168 documents
Dzīvības procesu ķīmiskie regulatori: vitamīni un hormoni
1948
Tulkojums no krievu valodas.
Natural approaches in metabolic syndrome management
2017
Metabolic syndrome (MetS) is characterized as a group of cardiometabolic risk factors that raise the risk for heart disease and other health problems, such as diabetes mellitus and stroke. Treatment strategies include pharmacologic interventions and supplementary (or "alternative") treatments. Nutraceuticals are derived from food sources (isolated nutrients, dietary supplements and herbal products) that are purported to provide health benefits, in addition to providing basic nutritional value. Nutraceuticals are claimed to prevent chronic diseases, improve health, delay the aging process, increase life expectancy, and support the structure and function of the body. The study of the benefici…
Refolding of the integral membrane protein light-harvesting complex II monitored by pulse EPR
2009
The major light-harvesting chlorophyll a / b complex (LHCII) of the photosynthetic apparatus in plants self-organizes in vitro. The recombinant apoprotein, denatured in dodecyl sulfate, spontaneously folds when it is mixed with its pigments, chlorophylls, and carotenoids in detergent solution, and assembles into structurally authentic LHCII in the course of several minutes. Pulse EPR techniques, specifically double-electron-electron resonance (DEER), have been used to analyze protein folding during this process. Pairs of nitroxide labels were introduced site-specifically into recombinant LHCII and shown not to affect the stability and function of the pigment-protein complex. Interspin dist…
Antioxidants: Role in the prevention and treatment of bronchopulmonary dysplasia
2022
Bronchopulmonary dysplasia (BPD) is one of the major causes of chronic respiratory diseases among infants. Both pharmacological and nonpharmacological approaches have been proposed for its management. Since oxidative stress is known to play a pivotal role in the pathogenesis of BPD, it is reasonable to consider the potential of antioxidant strategies in the prevention and treatment of this condition. Indeed, antioxidants can prevent or inhibit substrate oxidation. Some studies have evaluated the efficacy of the exogenous administration of vitamins and micronutrients in reducing the propagation of free radicals through their scavenging capacity. Nonetheless, encouraging preclinical results d…
Determination of liposoluble vitamins in cooked meals, milk and milk products by liquid chromatography
2002
A method for the simultaneous determination of liposoluble vitamins in cooked meals was established. Saponification was performed with 50% (w/v) KOH at 80 degrees C, and ascorbic acid was added as antioxidant. The subsequent extraction was carried out with diethyl ether. This was followed by a liquid chromatographic separation on a reversed-phase C18 column with methanol-water (94:6, v/v as the mobile phase. Retinyl acetate was used as the internal standard. The analytical parameters linearity, detection limit (0.19 and 8.33 microg/100 g for retinol and alpha-tocopherol, respectively), precision of the method (RSD=5.24 and 6.99% for retinol and alpha-tocopherol, respectively) and recovery a…
Priming of plant resistance by natural compounds. Hexanoic acid as a model
2014
Some alternative control strategies of currently emerging plant diseases are based on the use of resistance inducers. This review highlights the recent advances made in the characterization of natural compounds that induce resistance by a priming mechanism. These include vitamins, chitosans, oligogalacturonides, volatile organic compounds, azelaic and pipecolic acid, among others. Overall, other than providing novel disease control strategies that meet environmental regulations, natural priming agents are valuable tools to help unravel the complex mechanisms underlying the induced resistance (IR) phenomenon. The data presented in this review reflect the novel contributions made from studyin…
Inhibition of the mutagenicity of 2-nitrofluorene, 3-nitrofluoranthene and 1-nitropyrene by vitamins, porphyrins and related compounds, and vegetable…
1997
When 21 vitamins including related compounds haemin, chlorophyllin, chlorophyll, biliverdin and bilirubin, as well as juices from five fruits and 25 vegetables and solvent extracts from the residues of fruits and vegetables were tested for their antimutagenic potencies with respect to mutagenicity induced by 2-nitrofluorene (2-NF), 3-nitrofluoranthene (3-NFA) and 1-nitropyrene(1-NP) in Salmonella typhimurium TA98 the following results were obtained. The tetracyclic nitroarenes 3-NFA and 1-NP were in general more effectively antagonized by potent antimutagenic compounds than the tricyclic 2-NF. beta-Carotene, retinol, retinal, retinoic acid, retinol palmitate, riboflavin 5'-phosphate, alpha-…
Effect of Calcifediol on Physical Performance and Muscle Strength Parameters: A Systematic Review and Meta-Analysis
2022
There is general agreement that optimal vitamin D status is necessary for bones, muscles, and general health, particularly in older adults, who are at higher risk of negative consequences of vitamin D deficiency, including sarcopenia; vitamin D supplementation is proposed as a potential intervention to mitigate sarcopenia. Several RCTs have reported that calcifediol (25(OH)D) was more potent than cholecalciferol in increasing plasma 25(OH)D. The present systematic review and meta-analysis aimed to summarize the effects of calcifediol on physical performance and muscle strength. We searched databases from inception to 1 January 2022 for studies investigating calcifediol on physical performan…
Changes associated with aging and replicative senescence in the regulation of transcription factor nuclear factor-kappa B.
1996
Both the aging of animals and the senescence of cultured cells involve an altered pattern of gene expression, suggesting changes in transcription factor regulation. We studied age-related changes in transcription factors nuclear factor (NF)-kappa B, activator protein factor-1 (AP-1) and Sp-1 by using electrophoretic mobility shift binding assays; we also analysed changes in the protein components of NF-kappa B complex with Western blot assays. Nuclear and cytoplasmic extracts were prepared from heart, liver, kidney and brain of young adult and old NMRI mice and Wistar rats as well as from presenescent, senescent and simian virus 40-immortalized human WI-38 fibroblasts. Aging of both mice an…
Age-related changes in the regulation of transcription factor NF-kappa B in rat brain.
1997
Aging process involves an increase in stress at cellular level. We studied whether aging affects the regulation of stress responsive transcription factor NF-kappa B in brain samples of Wistar rats. Hippocampus, cerebellum, and temporal and frontal lobes of cortex were studied. We observed a significant up-regulation in the constitutive, nucleus-located NF-kappa B binding activity in 30-month-old Wistar rats compared to young and 18-month-old rats. The increase was most prominent in cerebellum and in frontal cortex, but age-related changes did not occur in hippocampus. Inducible, cytoplasmic NF-kappa B binding activity was not affected by aging in any of the samples studied. Western blot ass…