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Fish oil and vitamin E supplementation in oxidative stress at rest and after physical exercise 总被引:1,自引:0,他引:1
Sen Chandan K.; Atalay Mustafa; Agren Jyrki; Laaksonen David E.; Roy Sashwati; Hanninen Osmo 《Journal of applied physiology》1997,83(1):189-195
Sen, Chandan K., Mustafa Atalay, Jyrki Ågren,David E. Laaksonen, Sashwati Roy, and Osmo Hänninen. Fishoil and vitamin E supplementation in oxidative stress at rest and afterphysical exercise. J. Appl. Physiol.83(1): 189-195, 1997.Fish oil supplementation and physicalexercise may induce oxidative stress. We tested the effects of 8 wk of-tocopherol (vitamin E) and fish oil (FO) supplementation on resting and exercise-induced oxidative stress. Rats(n = 80) were divided into groupssupplemented with FO, FO and vitamin E (FOVE), soy oil (SO), and SO andvitamin E (SOVE), and for FOVE and SOVE they were dividedinto corresponding exercise groups (FOVE-Ex and SOVE-Ex). Lipidperoxidation [thiobarbituric acid-reacting substances(TBARS)] was 33% higher in FO compared with SO in the liver, butoxidative protein damage (carbonyl levels) remained similar in bothliver and red gastrocnemius muscle (RG). Vitamin E supplementation,compared with FO and SO, markedly decreased liver and RG TBARS, butliver TBARS remained 32% higher in FOVE vs. SOVE. Vitamin E alsomarkedly decreased liver and RG protein carbonyl levels, althoughlevels in FOVE and SOVE were similar. Exercise increased liver and RGTBARS and RG protein carbonyl levels markedly, with similar levels inFOVE-Ex and SOVE-Ex. FO increased lipid peroxidation but not proteinoxidation in a tissue-specific manner. Vitamin E markedly decreasedlipid peroxidation and protein oxidation in both FOVE and SOVE,although liver lipid peroxidation remained higher in FOVE. Despitehigher levels of hepatic lipid peroxidation at rest in FOVE comparedwith SOVE, liver appeared to be relatively less susceptible toexercise-induced oxidative stress in FOVE. 相似文献
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Anna Halenius Satu Lakio Osmo Antikainen Juha Hatara Jouko Yliruusi 《AAPS PharmSciTech》2014,15(3):781-791
In this paper, linkages between tablet surface roughness, tablet compression forces, material properties, and the tensile strength of tablets were studied. Pure sodium halides (NaF, NaBr, NaCl, and NaI) were chosen as model substances because of their simple and similar structure. Based on the data available in the literature and our own measurements, various models were made to predict the tensile strength of the tablets. It appeared that only three parameters—surface roughness, upper punch force, and the true density of material—were needed to predict the tensile strength of a tablet. Rather surprising was that the surface roughness alone was capable in the prediction. The used new 3D imaging method (Flash sizer) was roughly a thousand times quicker in determining tablet surface roughness than traditionally used laser profilometer. Both methods gave practically analogous results. It is finally suggested that the rapid 3D imaging can be a potential in-line PAT tool to predict mechanical properties of tablets in production. 相似文献
24.
Sirpa Vuorinen Jyrki Heinämäki Osmo Antikainen Mohammed Lahcini Timo Repo Jouko Yliruusi 《AAPS PharmSciTech》2009,10(2):566-573
Sugar end-capped poly-d,l-lactide (SPDLA) polymers were investigated as a potential release controlling excipient in oral sustained release matrix
tablets. The SPDLA polymers were obtained by a catalytic ring-opening polymerization technique using methyl α-d-gluco-pyranoside as a multifunctional initiator in the polymerization. Polymers of different molecular weights were synthesized
by varying molar ratios of monomer/catalyst. The matrix tablets were prepared by direct compression technique from the binary
mixtures of SPDLA and microcrystalline cellulose, and theophylline was used as a model drug. The tablet matrices showed in vitro reproducible drug release profiles with a zero-order or diffusion-based kinetic depending on the SPDLA polymer grade used.
Further release from the tablet matrices was dependent on the molecular weight of the SPDLA polymer applied. The drug release
was the fastest with the lowest molecular weight SPDLA grade, and the drug release followed zero-order rate. With the higher
molecular weight SPDLAs, more prolonged dissolution profiles for the matrix tablets (up to 8–10 h) were obtained. Furthermore,
the prolonged drug release was independent of the pH of the dissolution media. In conclusion, SPDLAs are a novel type of drug
carrier polymers applicable in oral controlled drug delivery systems. 相似文献
25.
Natalja Genina Heikki Räikkönen Osmo Antikainen Jyrki Heinämäki Jouko Yliruusi 《AAPS PharmSciTech》2010,11(3):1320-1327
An ultrasound-assisted powder-coating technique was used to produce a homogeneous powder formulation of a low-dose active pharmaceutical ingredient (API). The powdered particles of microcrystalline cellulose (MCC; Avicel® PH-200) were coated with a 4% m/V aqueous solution of riboflavin sodium phosphate, producing a uniform drug layer on the particle surfaces. It was possible to regulate the amount of API in the treated powder. The thickness of the API layer on the surface of the MCC particles increased near linearly as the number of coating cycles increased, allowing a precise control of the drug content. The tablets (n = 950) prepared from the coated powder showed significantly improved weight and content uniformity in comparison with the reference tablets compressed from a physical binary powder mixture. This was due to the coated formulation remaining uniform during the entire tabletting process, whereas the physical mixture of the powders was subject to segregation. In conclusion, the ultrasound-assisted technique presented here is an effective tool for homogeneous drug coating of powders of irregular particle shape and broad particle size distribution, improving content uniformity of low-dose API in tablets, and consequently, ensuring the safe delivery of a potent active substance to patients.Key words: content uniformity, homogeneity, low-dose API, powder coating, ultrasound 相似文献
26.
Hakosalo H 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2006,37(2):172-202
Major changes took place during the last quarter of the nineteenth century in the ways that the brain tissue was maintained, manipulated and studied, and, consequently, in the ways that its structure, functions and pathologies were seen and represented in neurological literature. The paper exemplifies these changes by comparing German neuroanatomy in the 1860s and early 1870s (represented above all by Theodor Meynert) with the turn-of-the-century view of the brain (represented by Constantin von Monakow and others). It argues for the crucial importance of a method--serial sectioning--to the emergence of the new view of the brain. Serial sectioning in turn owes its existence to the new techniques in staining and sectioning that were introduced in the 1870s and 1880s. In particular, the paper highlights the role of a cutting device, the microtome, in enabling serial sectioning and in thereby contributing to the emergence of a new view of the brain. 相似文献
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Liimatainen H Sirviö J Sundman O Visanko M Hormi O Niinimäki J 《Bioresource technology》2011,102(20):9626-9632
The flocculation behavior of cationic, quaternary ammonium groups containing cellulosic biopolymers, CDACs, synthesized by cationizing dialdehyde cellulose in mild aqueous solution was studied in a kaolin suspension. In particular, the role of CDAC dosage and solution pH, NaCl concentration, and temperature were clarified. In addition, the initial apparent charge densities (CDs), particle sizes, ζ-potential, and stability of CDs were determined. CDACs possessed a high flocculation activity in neutral and acidic solutions, but a significant decrease was observed in alkaline solutions (pH >9). This was also seen as a decline in the apparent CD and particle size of the CDACs in alkaline conditions. The measurements also indicated that the apparent CD decreased to a constant level of 3 mmol/g in aqueous solutions. However, no notable decrease in flocculation performance was obtained after several days of storage. Moreover, the variation of NaCl concentration and temperature did not affect the flocculation activity. 相似文献
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Saija J. Ahonen Meharji Arumilli Eija Sepp?l? Osmo Hakosalo Maria K. Kaukonen András M. Komáromy Hannes Lohi 《PloS one》2014,9(12)
Progressive retinal degenerations are among the most common causes of blindness both in human and in dogs. Canine progressive retinal atrophy (PRA) resembles human retinitis pigmentosa (RP) and is typically characterized by a progressive loss of rod photoreceptors followed by a loss of cone function. The disease gradually progress from the loss of night and day vision to a complete blindness. We have recently described a unique form of retinopathy characterized by the multifocal gray/brown discoloration and thinning of the retina in the Swedish Vallhund (SV) breed. We aimed to identify the genetic cause by performing a genome wide association analysis in a cohort of 18 affected and 10 healthy control dogs using Illumina''s canine 22k SNP array. We mapped the disease to canine chromosome 17 (p = 7.7×10−5) and found a 6.1 Mb shared homozygous region in the affected dogs. A combined analysis of the GWAS and replication data with additional 60 dogs confirmed the association (p = 4.3×10−8, OR = 11.2 for homozygosity). A targeted resequencing of the entire associated region in four cases and four controls with opposite risk haplotypes identified several variants in the coding region of functional candidate genes, such as a known retinopathy gene, MERTK. However, none of the identified coding variants followed a compelling case- or breed-specific segregation pattern. The expression analyses of four candidate genes in the region, MERTK, NPHP1, ANAPC1 and KRCC1, revealed specific upregulation of MERTK in the retina of the affected dogs. Collectively, these results indicate that the retinopathy is associated with overexpression of MERTK, however further investigation is needed to discover the regulatory mutation for the better understanding of the disease pathogenesis. Our study establishes a novel gain-of-function model for the MERTK biology and provides a therapy model for retinopathy MERTK inhibitors. Meanwhile, a marker-based genetic counseling can be developed to revise breeding programs. 相似文献
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Cervera MF Heinämäki J de la Paz N López O Maunu SL Virtanen T Hatanpää T Antikainen O Nogueira A Fundora J Yliruusi J 《AAPS PharmSciTech》2011,12(2):637-649
The effects of spray-drying process and acidic solvent system on physicochemical properties of chitosan salts were investigated.
Chitosan used in spray dryings was obtained by deacetylation of chitin from lobster (Panulirus argus) origin. The chitosan acid salts were prepared in a laboratory-scale spray drier, and organic acetic acid, lactic acid, and
citric acid were used as solvents in the process. The physicochemical properties of chitosan salts were investigated by means
of solid-state CP-MAS 13C nuclear magnetic resonance (NMR), X-ray powder diffraction (XRPD), differential scanning calorimetry, and Fourier transform
infrared spectrometry (FTIR) and near-infrared spectroscopy. The morphology of spray-dried chitosan acid salts showed tendency
toward higher sphericity when higher temperatures in a spray-drying process were applied. Analysis by XRPD indicated that
all chitosan acid salts studied were amorphous solids. Solid-state 13C NMR spectra revealed the evidence of the partial conversion of chitosan acetate to chitin and also conversion to acetyl
amide form which appears to be dependent on the spray-drying process. The FTIR spectra suggested that the organic acids applied
in spray drying may interact with chitosan at the position of amino groups to form chitosan salts. With all three chitosan
acid salts, the FTIR bands at 1,597 and 1,615 cm−1 were diminished suggesting that –NH groups are protonated. The FTIR spectra of all chitosan acid salts exhibited ammonium
and carboxylate bands at 1,630 and 1,556 cm−1, respectively. In conclusion, spray drying is a potential method of preparing acid salts from chitosan obtained by deacetylation
of chitin from lobster (P. argus) origin. 相似文献
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Anna Penkina Osmo Antikainen Maija Hakola Sirpa Vuorinen Timo Repo Jouko Yliruusi Peep Veski Karin Kogermann Jyrki Heinämäki 《AAPS PharmSciTech》2013,14(3):1129-1136
Tablet compression of softwood cellulose and lignin prepared by a new catalytic oxidation and acid precipitation method were investigated and compared with the established pharmaceutical direct compression excipients. Catalytic pretreated softwood cellulose (CPSC) and lignin (CPSL) were isolated from pine wood (Pinus sylvestris). The compaction studies were carried out with an instrumented eccentric tablet machine. The plasticity and elasticity of the materials under compression were evaluated using force-displacement treatment and by determining characteristic plasticity (PF) and elasticity (EF) factors. With all biomaterials studied, the PF under compression decreased exponentially as the compression force increased. The compression force applied in tablet compression did not significantly affect the elasticity of CPSC and microcrystalline cellulose (MCC) while the EF values for softwood lignins increased as compression force increased. CPSL was clearly a less plastically deforming and less compactable material than the two celluloses (CPSC and MCC) and hardwood lignin. CPSL presented deformation and compaction behaviour almost identical to that of lactose monohydrate. In conclusion, the direct tablet compression behaviour of native lignins and celluloses can greatly differ from each other depending on the source and isolation method used. 相似文献