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91.
Cheng-yi Lii Chia-ding Liao Leszek Stobinski Piotr Tomasik 《Carbohydrate polymers》2002,49(4):449-456
Cassava, corn, high amylose corn, potato, rice Indica, rice Japonica, sweet potato, waxy corn, and wheat starches were exposed to low-pressure ammonia, hydrogen, and oxygen plasma. In every case, depolymerization of the starch polysaccharides was noted. The extent of the depolymerization depended on the nature of the starch as well as the type of plasma applied. Among three fractions of polysaccharides distinguished by their molecular weight average, the fraction of the highest molecular weight suffered the most efficient depolymerization. The relative depolymerization for the middle- and low-molecular fractions of polysaccharides was found to be starch and plasma specific. The chemical character of the plasma had very little influence on the starch polysaccharides. Only subtle oxidation effects were observed in oxygen plasma. Low-pressure glow plasma treatment appeared to be a convenient tool for a waste-less dextrinization of starch. Manipulation of the plasma variety and the time of exposure resulted in a wide spectrum of dextrins of various molecular weights and paste-forming properties. 相似文献
92.
Leszek Lisowski Menashe Elazar Kirk Chu Jeffrey S. Glenn Mark A. Kay 《Nucleic acids research》2013,41(6):3688-3698
Hepatitis C Virus (HCV) and other plus-strand RNA viruses typically require the generation of a small number of negative genomes (20–100× lower than the positive genomes) for replication, making the less-abundant antigenome an attractive target for RNA interference(RNAi)-based therapy. Because of the complementarity of duplex short hairpin RNA/small interfering RNA (shRNA/siRNAs) with both genomic and anti-genomic viral RNA strands, and the potential of both shRNA strands to become part of the targeting complexes, preclinical RNAi studies cannot distinguish which viral strand is actually targeted in infected cells. Here, we addressed the question whether the negative HCV genome was bioaccessible to RNAi. We first screened for the most active shRNA molecules against the most conserved regions in the HCV genome, which were then used to generate asymmetric anti-HCV shRNAs that produce biologically active RNAi specifically directed against the genomic or antigenomic HCV sequences. Using this simple but powerful and effective method to screen for shRNA strand selectivity, we demonstrate that the antigenomic strand of HCV is not a viable RNAi target during HCV replication. These findings provide new insights into HCV biology and have important implications for the design of more effective and safer antiviral RNAi strategies seeking to target HCV and other viruses with similar replicative strategies. 相似文献
93.
Tomasz Oniszczuk Anna Oniszczuk Ewa Gondek Leszek Guz Krzysztof Puk Anna Kocira Andrzej Kusz Kamila Kasprzak Agnieszka Wójtowicz 《Saudi Journal of Biological Sciences》2019,26(1):24-30
The growth of fish is directly dependent on feed composition and quality. Medicinal plants can be added to fish feed as adjuvant therapy for the prevention of fish diseases. The purple coneflower (Echinacea purpurea (L.) Moench.) has been reported to have multiple biological effects, including immunomodulatory and antioxidant activity. The most active compounds of E. purpurea are polyphenols - caffeic acid derivatives: caftaric acid, chlorogenic acid, cynarin, echinacoside and cichoric acid.Due to a relatively limited number of studies on the use of the purple coneflower as a nutritional supplement for fish feeding, extruded fish feed with addition of Echinacea roots was produced. In the feed total phenolic content, selected polyphenol contents, the energetic value, nutrient contents and antioxidant capacity were examined.The results indicate that fish feed with addition of the Echinacea has a great potential to be a good source of natural radical scavengers, for example polyphenols, and nutritive ingredients. Antioxidant properties of feed were well correlated with the coneflower content. The study findings confirmed that high-temperature extrusion-cooking process does not deactivate phenolic antioxidant compounds, which are present both in the Echinacea roots and in the final product. Fish feed with addition of E. purpurea can be used as a nutritional supplement in the prevention of fish diseases caused by oxidative stress. 相似文献
94.
Abstract The conversion of the benzoylated cAMP (2) to the diastereomeric mixture of the anilidates (3) was improved. Replacing the triphenylphosphine/carbon tetrachloride mixture by oxalyl chloride in the presence of a catalytic amount of DMF followed by the addition of aniline not only increased the yield from 27 to 96% but rendered much easier the separation of the diastereoisomers (3), which were formed in approximately equal amounts. This greatly improved the accessability of Rp and Sp-cAMPS (1). 相似文献
95.
Barbara Wegiel Thomas Jiborn Magnus Abrahamson Leszek Helczynski Leo Otterbein Jenny Liao Persson Anders Bjartell 《PloS one》2009,4(11)
Cystatin C is believed to prevent tumor progression by inhibiting the activities of a family of lysosomal cysteine proteases. However, little is known about the precise mechanism of cystatin C function in prostate cancer. In the present study, we examined the expression of cystatin C and its association with matrix metalloproteinases 2 (MMP2) and androgen receptor (AR) in a tissue microarray comparing benign and malignant specimens from 448 patients who underwent radical prostatectomy for localized prostate cancer. Cystatin C expression was significantly lower in cancer specimens than in benign tissues (p<0.001) and there was a statistically significant inverse correlation between expression of cystatin C and MMP2 (rs
2 = −0.056, p = 0.05). There was a clear trend that patients with decreased level of cystatin C had lower overall survival. Targeted inhibition of cystatin C using specific siRNA resulted in an increased invasiveness of PC3 cells, whereas induction of cystatin C overexpression greatly reduced invasion rate of PC3 in vitro. The effect of cystatin C on modulating the PC3 cell invasion was provoked by Erk2 inhibitor that specifically inhibited MAPK/Erk2 activity. This suggests that cystatin C may mediate tumor cell invasion by modulating the activity of MAPK/Erk cascades. Consistent with our immunohistochemical findings that patients with low expression of cystatin C and high expression of androgen receptor (AR) tend to have worse overall survival than patients with high expression of cystatin C and high AR expression, induced overexpression of AR in PC3 cells expressing cystatin C siRNA greatly enhanced the invasiveness of PC3 cells. This suggests that there may be a crosstalk between cystatin C and AR-mediated pathways. Our study uncovers a novel role for cystatin C and its associated cellular pathways in prostate cancer invasion and metastasis. 相似文献
96.
Kawalec Tomasz Sierant Aleksandra Panaś Roman Fiutowski Jacek Bartoszek-Bober Dobrosława Józefowski Leszek Rubahn Horst-Günter 《Plasmonics (Norwell, Mass.)》2018,13(2):639-644
Plasmonics - We report on an optical mirror for cold rubidium atoms based on a repulsive dipole potential created by means of a modified recordable digital versatile disc. Using the mirror, we have... 相似文献
97.
Inside Cover: Optimized perfusion‐based CUBIC protocol for the efficient whole‐body clearing and imaging of rat organs (J. Biophotonics 5/2018) 下载免费PDF全文
Paweł Matryba Lukasz Bozycki Monika Pawłowska Leszek Kaczmarek Marzena Stefaniuk 《Journal of biophotonics》2018,11(5)
Optical tissue clearing is a method allowing post‐mortem deep imaging of organs in three dimensions. By optimizing the CUBIC clearing protocol, the authors provide rapid and simple approach to clear the entire adult rat organism within as little as four days, which is accompanied by the variety of its staining and imaging techniques. The image was captured with polarizers and demonstrates transparent rodent heart with thread‐like crystals of clearing reagent. Further details can be found in the article by Pawe? Matryba et al. ( e201700248 ).
98.
Ferdinand Bohlmann Christa Zdero Jasmin Jakupovic Laxmi N. Misra Shanta Banerjee Pahup Singh Robindra N. Baruah Mohamed A. Metwally Guillermo Schmeda-Hirschmann Leszek P.D. Vincent Robert M. King Harold Robinson 《Phytochemistry》1985,24(6):1249-1261
The investigation and reinvestigation respectively of 23 Senecio species afforded 11 further cacalol derivatives, a furoeremophilone, 17 eremophilanes, 4 bisabolene derivatives, a shikimic acid derivative, a bis-prenylated p-hydroxybenzaldehyde, menth-2-en- 1,7-diol and a cumol derivative. The configuration of some eremophilanes have been revised. Structures were elucidated by spectroscopic methods. The results are summarized in a table. The chemotaxonomic aspects agree with those of previous investigations. 相似文献
99.
?ukasz J. Sznajder Micha? Michalak Katarzyna Taylor Piotr Cywoniuk Micha? Kabza Agnieszka Wojtkowiak-Szlachcic Magdalena Mat?oka Patryk Konieczny Krzysztof Sobczak 《Nucleic acids research》2016,44(21):10326-10342
Muscleblind-like (MBNL) proteins are critical RNA processing factors in development. MBNL activity is disrupted in the neuromuscular disease myotonic dystrophy type 1 (DM1), due to the instability of a non-coding microsatellite in the DMPK gene and the expression of CUG expansion (CUGexp) RNAs. Pathogenic interactions between MBNL and CUGexp RNA lead to the formation of nuclear complexes termed foci and prevent MBNL function in pre-mRNA processing. The existence of multiple MBNL genes, as well as multiple protein isoforms, raises the question of whether different MBNL proteins possess unique or redundant functions. To address this question, we coexpressed three MBNL paralogs in cells at equivalent levels and characterized both specific and redundant roles of these proteins in alternative splicing and RNA foci dynamics. When coexpressed in the same cells, MBNL1, MBNL2 and MBNL3 bind the same RNA motifs with different affinities. While MBNL1 demonstrated the highest splicing activity, MBNL3 showed the lowest. When forming RNA foci, MBNL1 is the most mobile paralog, while MBNL3 is rather static and the most densely packed on CUGexp RNA. Therefore, our results demonstrate that MBNL paralogs and gene-specific isoforms possess inherent functional differences, an outcome that could be enlisted to improve therapeutic strategies for DM1. 相似文献
100.
Boncler M Gresner P Nocun M Rywaniak J Dolnik M Rysz J Wilk R Czyz M Markuszewski L Banach M Watala C 《Biochimica et biophysica acta》2007,1770(12):1651-1659
We describe the role of plasma and platelet cholesterol content in the ability of acetylsalicylic acid (ASA) to acetylate platelet proteins and inhibit platelet function. Platelet susceptibility to ASA was monitored in subjects differing in plasma total cholesterol and in suspensions of cholesterol-enriched or cholesterol-depleted platelets. Platelets from subjects with higher plasma cholesterol (>6 mmol/l) showed reduced platelet sensitivity to ASA (inhibition of platelet aggregation and thromboxane generation by 60% and 68% in 'lower-' vs. 32% and 56% in 'higher-cholesterol' donors; n=13 in each group; p=0.056 and p<0.04, respectively). [Acetyl-1-(14)C] incorporation to platelet proteins in subjects with higher plasma cholesterol was significantly reduced (11.0 vs. 14.6 nmol/g protein, p<0.0001) and correlated significantly with blood total cholesterolemia (R(K)=-0.430, p<0.003) and LDL-cholesterol (R(K)=-0.349, p<0.012), but not with platelet cholesterol content. In conclusion, elevated plasma cholesterol is an important determinant of ASA-induced acetylation of platelets and platelet diminished sensitivity to ASA. The molecular basis of such an association remains obscure, notwithstanding it may constitute a link between sub-optimal platelet response to aspirin and lipid metabolic disorders. 相似文献