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排序方式: 共有1494条查询结果,搜索用时 15 毫秒
51.
Aleksandra Maria Staszak Tomasz Andrzej Paw?owski 《International journal of molecular sciences》2014,15(6):10868-10891
The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF). Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin) associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association. 相似文献
52.
53.
Anna Rzepkowska Aleksandra Ołdak Danuta Kołożyn-Krajewska 《International Journal of Food Properties》2017,20(11):2736-2747
Twenty-one strains of the genus Lactobacillus and the genus Pediococcus, isolated from Polish raw fermented meat products, were examined for the potential probiotic properties: resistance to simulated gastric and intestine conditions, safety assessment, and antimicrobial properties. Strains were resistant to gastric enzymes and low pH (3–6 log CFU/mL decrease) and intestinal enzymes and bile salts (1–3 log CFU/mL decrease). Most strains were resistant to gentamycin, streptomycin, vancomycin, tetracycline, ciprofloxacin, and kanamycin. Three of them (Lb. brevis BAL1, BAL10, and KL5) produced β-glucuronidase, which excludes them from qualifying as safe. Seven strains had the ability to produce bacteriocins or bacteriocin-like substances. Overall, strains Lb. brevis SCH6, Pd. pentosaceus BAL6, and KL14 revealed selected superior characteristics (resistance to the gastrointestinal conditions, safety assessment, and antimicrobial properties) as compared to the other LAB strains investigated, which made them a viable bioprotective culture that can be inoculated in raw fermented meat products as starter cultures. 相似文献
54.
Mihajlo C. Stefanovic Jelena A. Anastasov Aleksandra M. Cvetkovic Goran T. Djordjevic 《Wireless Communications and Mobile Computing》2015,15(18):2141-2149
The outage performance of the amplify‐and‐forward relaying strategies over mutually uncorrelated extended generalized‐K fading channels is addressed in this paper. The attention is dedicated to the analyses of the noise‐limited and also interference‐limited environment. The new analytical expression for outage probability of observed relaying system in the presence of thermal noise is derived using the method for approximating equivalent signal‐to‐noise ratio. In addition, the outage performance is studied for the dual‐hop system when only the single dominant co‐channel interference is inherent at the relay and destination node. The correctness of the proposed mathematical derivations is verified by simulations. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
55.
Viscoelastic properties of poly(ε‐caprolactone)/clay nanocomposites in solid and in melt state 下载免费PDF全文
Viscoelastic properties in solid and in melt state of poly(ε‐caprolactone), PCL, nanocomposites with organomodified clays (Cloisite30B and Cloisite15A) are thoroughly investigated. Although WAXD is insensitive to the difference in the nanocomposites structure, the melt rheology reveals pronounced differences between the two series. Melt yield stress values, obtained from fittings by the Carreau–Yasuda model, are used as a measure of partial exfoliation of the clay. Temperature dependence of the shift factors, used for time–temperature superposition of the modulus curves, yields similar values of the flow activation energies for all the samples. Temperature dependences of the dynamic modulus and loss factor of solid nanocomposites were correlated to the structural differences deduced from the melt rheology. The increase in the storage modulus is compared to the theoretical predictions from the Halpin–Tsai model. The effective aspect ratio obtained from this comparison agrees reasonably with the value estimated from the melt rheology. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42896. 相似文献
56.
Synthesis,spectroscopic characterisation,and potential application of dyes containing a carbostyril skeleton as sensors for thiols 下载免费PDF全文
Aleksandra Grzelakowska Jolanta Kolińska Jolanta Sokołowska 《Coloration Technology》2016,132(2):121-129
Several dyes based on a carbostyril skeleton were synthesised and characterised using proton nuclear magnetic resonance spectroscopy and electron ionisation mass spectrometry. Their basic spectroscopic properties, such as absorption and emission spectra, were also measured. The behaviour of the obtained dyes in the absence and presence of thiol amino acids and other compounds under various conditions were studied. These dyes contain various moieties in the structure, acting as Michael acceptors. Results show that the studied compounds have the potential to act as colorimetric sensors for thiols, but the benzothioazolium dyes are less effective than dicyanoethylene derivatives. 相似文献
57.
Alicja Tymczewska Bliss Ursula Furtado Jacek Nowaczyk Katarzyna Hrynkiewicz Aleksandra Szydowska-Czerniak 《International journal of molecular sciences》2022,23(5)
This study aimed to develop and characterize gelatin/polyvinyl alcohol (G/PVA) films loaded with black cumin cake extract (BCCE) and zinc oxide nanoparticles (ZnONPs). The BCCE was also applied for the green synthesis of ZnONPs with an average size of less than 100 nm. The active films were produced by a solvent-casting technique, and their physicochemical and antibacterial properties were investigated. Supplementation of G/PVA film in ZnONPs decreased the tensile strength (TS) from 2.97 MPa to 1.69 MPa. The addition of BCCE and ZnONPs increased the elongation at the break (EAB) of the enriched film by about 3%. The G/PVA/BCCE/ZnONPs film revealed the lowest water vapor permeability (WVP = 1.14 × 10−9 g·mm·Pa−1·h−1·mm−2) and the highest opacity (3.41 mm−1). The QUick, Easy, New, CHEap and Reproducible (QUENCHER) methodologies using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) and cupric ion reducing antioxidant capacity (CUPRAC) were applied to measure antioxidant capacity (AC) of the prepared films. The incorporation of BCCE and ZnONPs into G/PVA films enhanced the AC by 8–144%. The films containing ZnONPs and a mixture of BCCE and ZnONPs inhibited the growth of three Gram-positive bacterial strains. These nanocomposite films with desired functional properties can be recommended to inhibit microbial spoilage and oxidative rancidity of packaged food. 相似文献
58.
Pradeep Bhartiya Neha Kaushik Linh N. Nguyen Sander Bekeschus Kai Masur Klaus-Dieter Weltmann Nagendra Kumar Kaushik Eun Ha Choi 《International journal of molecular sciences》2022,23(6)
Excess amounts of redox stress and failure to regulate homeostatic levels of reactive species are associated with several skin pathophysiologic conditions. Nonmalignant cells are assumed to cope better with higher reactive oxygen and nitrogen species (RONS) levels. However, the effect of periodic stress on this balance has not been investigated in fibroblasts in the field of plasma medicine. In this study, we aimed to investigate intrinsic changes with respect to cellular proliferation, cell cycle, and ability to neutralize the redox stress inside fibroblast cells following periodic redox stress in vitro. Soft jet plasma with air as feeding gas was used to generate plasma-activated medium (PAM) for inducing redox stress conditions. We assessed cellular viability, energetics, and cell cycle machinery under oxidative stress conditions at weeks 3, 6, 9, and 12. Fibroblasts retained their usual physiological properties until 6 weeks. Fibroblasts failed to overcome the redox stress induced by periodic PAM exposure after 6 weeks, indicating its threshold potential. Periodic stress above the threshold level led to alterations in fibroblast cellular processes. These include consistent increases in apoptosis, while RONS accumulation and cell cycle arrest were observed at the final stages. Currently, the use of NTP in clinical settings is limited due to a lack of knowledge about fibroblasts’ behavior in wound healing, scar formation, and other fibrotic disorders. Understanding fibroblasts’ physiology could help to utilize nonthermal plasma in redox-related skin diseases. Furthermore, these results provide new information about the threshold capacity of fibroblasts and an insight into the adaptation mechanism against periodic oxidative stress conditions in fibroblasts. 相似文献
59.
Ivan Kreft Mateja Germ Aleksandra Golob Blanka Vombergar Francesco Bonafaccia Zlata Luthar 《International journal of molecular sciences》2022,23(7)
Tartary buckwheat (Fagopyrum tataricum Gaertn.) is grown in eastern and central Asia (the Himalayan regions of China, Nepal, Bhutan and India) and in central and eastern Europe (Luxemburg, Germany, Slovenia and Bosnia and Herzegovina). It is known for its high concentration of rutin and other phenolic metabolites. Besides the grain, the other aboveground parts of Tartary buckwheat contain rutin as well. After the mixing of the milled buckwheat products with water, the flavonoid quercetin is obtained in the flour–water mixture, a result of rutin degradation by rutinosidase. Heating by hot water or steam inactivates the rutin-degrading enzymes in buckwheat flour and dough. The low buckwheat protein digestibility is due to the high content of phenolic substances. Phenolic compounds have low absorption after food intake, so, after ingestion, they remain for some time in the gastrointestinal tract. They can act in an inhibitory manner on enzymes, degrading proteins and other food constituents. In common and Tartary buckwheat, the rutin and quercetin complexation with protein and starch molecules has an impact on the in vitro digestibility and the appearance of resistant starch and slowly digestible proteins. Slowly digestible starch and proteins are important for the functional and health-promoting properties of buckwheat products. 相似文献
60.
Milica Jovanovi Krivokua Aleksandra Viloti Mirjana Nacka-Aleksi Andrea Pirkovi Danica uji Janko Legner Dragana Dekanski
anka Boji-Trbojevi 《International journal of molecular sciences》2022,23(1)
Galectins are a family of conserved soluble proteins defined by an affinity for β-galactoside structures present on various glycoconjugates. Over the past few decades, galectins have been recognized as important factors for successful implantation and maintenance of pregnancy. An increasing number of studies have demonstrated their involvement in trophoblast cell function and placental development. In addition, several lines of evidence suggest their important roles in feto-maternal immune tolerance regulation and angiogenesis. Changed or dysregulated galectin expression is also described in pregnancy-related disorders. Although the data regarding galectins’ clinical relevance are still at an early stage, evidence suggests that some galectin family members are promising candidates for better understanding pregnancy-related pathologies, as well as predicting biomarkers. In this review, we aim to summarize current knowledge of galectins in early pregnancy as well as in pregnancy-related pathologies. 相似文献