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41.
The present study analyzed binding of Cu2+ to tetrapeptides in water solution at several levels of theoretical approximation. The methods used to study the energetic
and structural properties of the complexes in question include semiempirical hamiltonians, density functional theory as well
as ab initio approaches including electron correlation effects. In order to shed light on the character of interactions between
Cu2+ and peptides, which are expected to be mainly electrostatic in nature, decomposition of interaction energy into physically
meaningful components was applied. 相似文献
42.
Grochowska Anna Dunaj Justyna Pancewicz Sławomir Czupryna Piotr Majewski Piotr Wondim Mulugeta Tryniszewska Elżbieta Moniuszko-Malinowska Anna 《Experimental & applied acarology》2022,86(4):607-607
Experimental and Applied Acarology - 相似文献
43.
Kistler AD Siwy J Breunig F Jeevaratnam P Scherl A Mullen W Warnock DG Wanner C Hughes DA Mischak H Wüthrich RP Serra AL 《PloS one》2011,6(6):e20534
Female patients affected by Fabry disease, an X-linked lysosomal storage disorder, exhibit a wide spectrum of symptoms, which renders diagnosis, and treatment decisions challenging. No diagnostic test, other than sequencing of the alpha-galactosidase A gene, is available and no biomarker has been proven useful to screen for the disease, predict disease course and monitor response to enzyme replacement therapy. Here, we used urine proteomic analysis based on capillary electrophoresis coupled to mass spectrometry and identified a biomarker profile in adult female Fabry patients. Urine samples were taken from 35 treatment-naïve female Fabry patients and were compared to 89 age-matched healthy controls. We found a diagnostic biomarker pattern that exhibited 88.2% sensitivity and 97.8% specificity when tested in an independent validation cohort consisting of 17 treatment-naïve Fabry patients and 45 controls. The model remained highly specific when applied to additional control patients with a variety of other renal, metabolic and cardiovascular diseases. Several of the 64 identified diagnostic biomarkers showed correlations with measures of disease severity. Notably, most biomarkers responded to enzyme replacement therapy, and 8 of 11 treated patients scored negative for Fabry disease in the diagnostic model. In conclusion, we defined a urinary biomarker model that seems to be of diagnostic use for Fabry disease in female patients and may be used to monitor response to enzyme replacement therapy. 相似文献
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46.
Serlin Bruce S.; Lew Roger R.; Krasnoshtein Flora; Krol Justyna; Sumida Kevin D. 《Plant & cell physiology》1996,37(2):175-179
Red light mediates chloroplast movement and increased activityof calcium-activated potassium channels on the plasma membraneof the alga Mougeotia sp. (UTEX LB 734). When activation ismediated by phytochrome, a far-red light irradiation given sometime after the red light irradiation will reverse the effectof the red light, due to phytochrome photoreversibility. Wecharacterized the escape times (time required for loss of photoreversibility)for these two processes to compare the transduction pathwaysinvolved in chloroplast rotation and channel activation. Theescape time for chloroplast rotation was 2.5 min after red lightirradiation (red and far-red light irradiations were 30 s).For channel activation, shorter red and far-red light irradiations(10 s) had to be used to obtain an escape time of 20 s. Thedifference in the escape times suggests that there is relativelyrapid divergence in the transduction pathways leading from phytochromeactivation (only one molecular species of phytochrome is foundin Mougeotia) to each of the two responses in the same cellularsystem. Because channel activation occurs 24 min afterirradiation while the escape time is 20 s, it is unlikely thatphytochrome acts directly on the channel. (Received September 26, 1995; Accepted December 28, 1995) 相似文献
47.
Lekka M Gil D Dąbroś W Jaczewska J Kulik AJ Lekki J Stachura Z Stachura J Laidler P 《Journal of molecular recognition : JMR》2011,24(5):833-842
The expression of N‐cadherin, characteristic of various cancers, very often leads to changes in the cells' adhesive properties. Thus, we sought to find out if N‐cadherin expressed in various, but cancer‐related cells, differs in its functional properties that could contribute to variations in cells' phenotypes. In our work, measurements of an unbinding force of a single N‐cadherin molecule, probed with the same antibody both on a surface of living non‐malignant (HCV29) and malignant cells (T24) of bladder cancer, were carried out with the use of an atomic force microscopy. The results show the enhanced N‐cadherin level in T24 malignant cells (8.7% vs. 3.6% obtained for non‐malignant one), confirmed by the Western blot and the immunohistochemical staining. The effect was accompanied by changes in unbinding properties of an individual N‐cadherin molecule. Lower unbinding force values (26.1 ± 7.1 pN) in non‐malignant cells reveal less stable N‐cadherin complexes, as compared to malignant cells (61.7 ± 14.6 pN). This suggests the cancer‐related changes in a structure of the binding site of the antibody, located at the extracellular domain of N‐cadherin. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
48.
Małgorzata Zalewska Justyna Lema-Rumińska Natalia Miler Magdalena Gruszka Weronika Dąbal 《In vitro cellular & developmental biology. Plant》2011,47(3):375-378
The subject of investigation was Chrysanthemum x grandiflorum (Ramat.) Kitam., ‘Satinbleu’. Leaf explants and internodes were excised from the middle part of the donor sterile plant.
Two methods of explant inoculation were applied: explants were placed polarly and horizontally. Modified MS medium (Murashige
and Skoog 1962), supplemented with 11.4 μM indoleacetic acid and 2.7 μM 6-benzylaminopurine, were prepared to induce adventitious bud formation.
Four dates of explant inoculation on the medium were tested: January 15, April 15, July 15, and October 15. Thus, regeneration
occurred in winter, spring, summer, and autumn. In the present study, a more intensive regeneration in ‘Satinbleu’ chrysanthemum
was observed in summer and autumn than in spring and winter, irrespective of the kind of explant and the inoculation method. 相似文献
49.
Pancer K Ciaćka A Gut W Lipka B Mierzejewska J Milewska-Bobula B Smorczewska-Kiljan A Jahnz-Rózyk K Dzierzanowska D Madaliński K Litwińska B 《Polish journal of microbiology》2011,60(3):253-258
Respiratory Syncytial Virus (RSV) is one of the most common causes of lower respiratory tract infections in young children, immunocompromised patients (children and adults), patients with chronic respiratory diseases and elderly people. Reinfections occur throughout the life, but the severity of disease decreased with subsequent infection. The aim of this study was to analyze the frequency of RSV infections in two selected subpopulations: young children (below 5 y.) and adults with chronic respiratory diseases (25-87 y.). Nasopharyngeal swabs (334) collected from October 2008 to March 2010 were examined. The presence of RSV genome was determined by RT-PCR and the presence of RSV antigen by quick immunochromatographic test. Positive results of RT-PCR were found in 45.2% of all swabs: 48.6% samples in 2008; 41.5% in 2009; 50.8% in 2010. The highest frequency of RSV-positive samples was in fall-winter months, but differences in RSV epidemic seasons were found. In the first season (2008-2009) an increased number of RSV infections was observed from November 2008, but in the second season--from January 2010. Generally, the frequency of RSV-positive RT-PCR among children was 53%, among adults 25%. The highest difference was observed in the first three-month period of 2010. RT-PCR positive samples were found in 68.5% of children and 5.9% of adults. However, the RSV antigen was found in 44.4% of samples collected from adults in this period. Our results indicate that the contribution of RSV infections during epidemic season of respiratory tract infections in Poland was really high among children and adults. 相似文献
50.