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41.
Marta Izabela Jonas Alina Kurylowicz Zbigniew Bartoszewicz Wojciech Lisik Maurycy Jonas Zbigniew Wierzbicki Andrzej Chmura Piotr Pruszczyk Monika Puzianowska-Kuznicka 《International journal of molecular sciences》2015,16(10):25817-25830
Excess adiposity is associated with chronic inflammation, which takes part in the development of obesity-related complications. The aim of this study was to establish whether subcutaneous (SAT) or visceral (VAT) adipose tissue plays a major role in synthesis of pro-inflammatory cytokines. Concentrations of interleukins (IL): 1β, 6, 8 and 15 were measured at the protein level by an ELISA-based method and on the mRNA level by real-time PCR in VAT and SAT samples obtained from 49 obese (BMI > 40 kg/m2) and 16 normal-weight (BMI 20–24.9 kg/m2) controls. IL-6 and IL-15 protein concentrations were higher in SAT than in VAT for both obese (p = 0.003 and p < 0.0001, respectively) and control individuals (p = 0.004 and p = 0.001, respectively), while for IL-1β this was observed only in obese subjects (p = 0.047). What characterized obese individuals was the higher expression of IL-6 and IL-15 at the protein level in VAT compared to normal-weight controls (p = 0.047 and p = 0.016, respectively). Additionally, obese individuals with metabolic syndrome had higher IL-1β levels in VAT than did obese individuals without this syndrome (p = 0.003). In conclusion, concentrations of some pro-inflammatory cytokines were higher in SAT than in VAT, but it was the increased pro-inflammatory activity of VAT that was associated with obesity and metabolic syndrome. 相似文献
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Inga Miina Elise Sipeniece Magdalena Rudziska Anna Grygier Monika Radzimirska‐Graczyk Edte Kaufmane Dalija Seglia Gunrs Lcis Pawe Grna 《European Journal of Lipid Science and Technology》2020,122(4)
Tocopherols, phytosterols, carotenoids, and squalene are present in mature seeds of Japanese quince. Yet, little is known about the relationship between these compounds and oil yield during fruit and seed development. The profile change of lipophilic compounds during fruit and seed development in Japanese quince cultivars “Darius,” “Rondo,” and “Rasa” is investigated. It is shown here that during fruit and seed development, there is a significant reduction, three‐ to over tenfold, in the concentration of minor bioactive compounds in seed oil. It is recorded that delay between synthesis of tocopherols and oil in Japanese quince seeds during the fruit development results in a logarithmic relationship between the oil content and tocopherols concentration in the seed oil (R2 = 0.980). Similar trends are observed between oil yield and phytosterols, and carotenoids (R2 = 0.927 and R2 = 0.959, respectively). The profile of fatty acids during the development of the seeds significantly is changed. The reduction of linoleic, palmitic, and gondoic acids levels and increment of oleic acid is noted. The oil content, profile of fatty acids, and concentration of bioactive compounds in all three genotypes of Japanese quince do not change significantly statistically during the last month of fruit development. Practical Applications: Some fruits are harvested at different degrees of maturity mainly due to a logistic issue and uneven ripening of fruits, which affects the chemical composition of whole fruit including seeds. Therefore, it would be good to know how the chemical composition is changing in plant material during development especially in the last month before harvest. Production of Japanese quince continues to rise year to year and with it the volume of generated by‐products such as seeds. This study demonstrates how it changes the oil content, profile of fatty acid, and concentration of tocopherols, squalene, phytosterols, and carotenoids in the seeds and seed oil of three Japanese quince cultivars “Rondo,” “Darius,” and “Rasa” during plant development. The provided information can be very useful for the manufactories oriented on the processing of by‐products, mainly seeds, generated by other branches of industry, for instance, fruit‐processing. 相似文献
44.
Kiran Kousar Thomas Ljungdahl Alexander Wetzel Michael Dowhyj Hans Oskarsson Alex S. Walton Monika S. Walczak Robert Lindsay 《Journal of surfactants and detergents》2020,23(1):225-234
An optimized one-pot recipe has been developed to synthesize a surfactant molecule, referred to as OMID, consisting of an imidazoline head group and aliphatic tail, which is an exemplar corrosion inhibitor for carbon steel in acidic solutions. As evidenced by gas chromatography, 1H and 13C nuclear magnetic resonance, and Fourier-transform infrared data, a high-purity product was achieved without the use of either a solvent or catalyst. Critical micelle concentration values and corrosion inhibition efficiencies ( η %) were determined in aqueous solutions of hydrochloric acid and sulfuric acid using surface tensiometry and linear polarization resistance measurements, respectively. Hydrolysis of the imidazoline head group as a function of pH (0–11) was explored with ultraviolet–visible absorption spectroscopy. In addition, N 1s and C 1s X-ray photoelectron spectroscopy data were acquired from both surface-adsorbed OMID and a multilayer of the imidazoline head group of OMID. These latter data are highly relevant to those attempting to understand OMID inhibition chemistry. 相似文献
45.
Chemical analysis of volatiles emitted by Pinus svlvestris after induction by insect oviposition 总被引:1,自引:0,他引:1
Gas chromatography – mass spectrometry analyses of the headspace volatiles of Scots pine (Pinus sylvestris) induced by egg deposition of the sawfly Diprion pini were conducted. The odor blend of systemically oviposition-induced pine twigs, attractive for the eulophid egg parasitoid Chrysonotomyia ruforum, was compared to volatiles released by damaged pine twigs (control) that are not attractive for the parasitoid. The mechanical damage inflicted to the control twigs mimicked the damage by a sawfly female prior to egg deposition. The odor blend released by oviposition-induced pine twigs consisted of numerous mono- and sesquiterpenes, which all were also present in the headspace of the artificially damaged control twigs. A quantitative comparison of the volatiles from oviposition-induced twigs and controls revealed that only the amounts of (E)--farnesene were significantly higher in the volatile blend of the oviposition-induced twigs. Volatiles from pine twigs treated with jasmonic acid (JA) also attract the egg parasitoid. No qualitative differences were detected when comparing the composition of the headspace of JA-treated pine twigs with the volatile blend of untreated control twigs. JA-treated pine twigs released significantly higher amounts of (E)--farnesene. However, the JA treatment induced a significant increase of the amount of further terpenoid components. The release of terpenoids by pine after wounding, egg deposition, and JA treatment is discussed with special respect to (E)--farnesene. 相似文献
46.
Valery A. Isidorov Sławomir Bakier Ewa Pirożnikow Monika Zambrzycka Izabela Swiecicka 《Journal of chemical ecology》2016,42(6):475-485
Honey bees harvest resins from various plant species and use them in the hive as propolis. While there have been a number of studies concerning the chemical composition of this antimicrobial product, little is known about selective behavior and bee preference when different potential plant sources of resin are available. The main objective of this paper was to investigate some aspects of behavioral patterns of honeybees in the context of resin acquisition. Samples of propolis originating from temperate zones of Europe and the supposed botanical precursors of the product were analyzed. Taxonomical markers of bud resins of two white birch species, aspen, black poplar, horse-chestnut, black alder, and Scots pine were determined through GC-MS analysis. All these trees have been reported as sources of propolis, but comparisons of the chemical composition of their bud resins with the compositions of propolis samples from seven European countries have demonstrated the presence of taxonomical markers only from black poplar, aspen, and one species of birch. This suggests selective behavior during the collection of bud resins by honeybees. To examine the causes of such selectivity, the antimicrobial properties of bud resins were determined. Horse-chestnut resins had lower antimicrobial activity than the other resins which did not differ significantly. 相似文献
47.
Wulff Possart Detlef Fanter Monika Bauer Andreas Hartwig Otto-Diedrich Hennemann 《The Journal of Adhesion》2013,89(1-4):261-263
FTIR reflection spectroscopy was used to characterize thin films of a cyanurate prepolymer on evaporated aluminium and on silicon single crystal wafers. Both substrates are covered by their native oxides. The optical function of the prepolymer is derived from ATR measurements. The measured thin film reflectance spectra have to be interpreted in comparison with the corresponding bulk spectra obtained by simulation. All samples re-produce the bulk composition. The cyanate groups of the prepolymer are not involved in specific intermolecular interactions or in preferential orientation. This is also found for the triazine rings on Si. On Al, however, a considerable excess of triazine rings are oriented parallel to the interface. The vibration frequencies of the triazine groupings that are perpendicular to the Al substrate show a red shift to some 2–8 c?1. This special interaction effect does not occur on Si. Both the preferential orientation and the specific inter-molecular interaction act at least 100 nm into the prepolymer layer. 相似文献
48.
Bitumen modification was made with the activated crumb rubber concentrate and its efficacy was examined in terms of its consistency and rheological properties. It was found that softening point of the activated crumb rubber‐modified bitumen increased while its penetration and elastic recovery decreased compared with the nonactivated crumb rubber system. Based on contact angle results, the activated crumb rubber–bitumen system was found to be more wettable and exhibited better adhesion to the substrate than those of other systems. The shifting of glass transition temperature towards higher temperature and the occurrence of inter‐mix phases in the activated crumb rubber–bitumen system supported its superior temperature resistance. The difference in viscosity obtained between the activated and nonactivated crumb rubber systems is attributed to the high swelling of activated crumb rubber and its soluble fractions in the bitumen as viewed in scanning electron images. High complex modulus and low phase angle of the activated crumb rubber system over the entire range of temperatures indicated its reduced temperature susceptibility and more elasticity. The activated crumb rubber–bitumen system meets the requirements of commercial standard specification. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Chugh Nisha Kumar Manoj Haldar Subhasis Bhattacharya Monika Gupta R.S. 《SILICON》2022,14(3):1029-1038
Silicon - In the present communication, for the first time, applicability of Field Plate (FP) for Double Channel (DC) AlGaN/GaNHEMT is demonstrated. Impact of design space parameters such as field... 相似文献