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41.
Piotr K. Borkowski Joanna Brydak-Godowska Wojciech Basiak Karolina ?witaj Hanna ?arnowska-Prymek Maria Olszyńska-Krowicka Piotr Kajfasz Daniel Rabczenko 《PLoS neglected tropical diseases》2016,10(8)
PurposeTo assess the impact of intensive antifolate treatment, followed by secondary antifolate prophylaxis (A-SP) on the recurrence rate of toxoplasmic retinochoroiditis (TRC). To investigate whether there are any other factors potentially predisposing for recurrence.ResultsWhen secondary antifolate prophylaxis (A-SP) was instituted immediately after the treatment for TRC, the probability of 3-year recurrence–free survival after the first course of A-SP was 90.9%. A recurrence was most likely approximately 3.5 years after the first treatment. A univariate Cox regression model demonstrated that a risk for recurrence was 2.82 times higher (p = 0.02) in patients with retinal scars. In the multivariate analysis, the risk for recurrence was 2.41 higher (p = 0.06). In patients with haemorrhagic lesions the risk for recurrence was lower, aRR = 0.17 (approaching borderline statistical significance p = 0.08).ConclusionsWith the institution of A-SP of immediately after the intensive treatment for TRC, i.e. when a reactivation was most likely, there was no recurrence during A-SP. Following A-SP the recurrence rates were low and recurrence-free periods tended to be longer. The treatment regimen employed had a beneficial effect on the recurrence interval as it reduced and delayed the highest probability of recurrence. 相似文献
42.
Sroka Z Fecka I Cisowski W 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(11-12):826-832
Polyphenolic compounds such as eriocitrin, luteolin-7-O-rutinoside, diosmin, hesperidin, narirutin, isorhoifolin, rosmarinic and caffeic acids were identified in an aqueous extract (Ex) obtained from peppermint leaves (Menthae x piperitae folium). The content of polyphenols in Ex was as follows: eriocitrin 38%, luteolin-7-O-rutinoside 3.5%, hesperidin 2.9%, diosmin 0.8%, isorhoifolin 0.6%, narirutin 0.3%, rosmarinic acid 3.7% and caffeic acid 0.05%. The strongest antiradical activity (determined as DPPH* scavenging features) was observed for luteolin-7-O-rutinoside, eriocitrin and rosmarinic acid. Caffeic acid and hesperidin revealed a lower antiradical activity while isorhoifolin, narirutin and diosmin showed the lowest activity. The strongest anti-H2O2 activity was observed for eriocitrin, a little lower for rosmarinic acid. The rate of hydrogen peroxide scavenging activity displayed by luteolin-7-O-rutinoside and caffeic acid was lower than that of rosmarinic acids. Hesperidin appeared to be a very weak scavenger of hydrogen peroxide. Almost no anti-H2O2 activity was demonstrated for diosmin, narirutin and isorhoifolin. Among examined flavonoids, the strongest antiradical and anti-H2O2 activity was shown for compounds with two hydroxy groups bound to the Bring in ortho position in relation to each other. Replacement of one hydroxy group in the Bring with a methoxy group or removing one hydroxy group leads to decrease of antiradical and anti-H2O2 activity of flavonoids. Our results suggest that eriocitrin is a powerful peppermint antioxidant and a free radical scavenger. 相似文献
43.
Joanna Czapla-Masztafiak Jakub Szlachetko Christopher?J. Milne Ewelina Lipiec Jacinto Sá Thomas?J. Penfold Thomas Huthwelker Camelia Borca Rafael Abela Wojciech?M. Kwiatek 《Biophysical journal》2016,110(6):1304-1311
The biological influence of radiation on living matter has been studied for years; however, several questions about the detailed mechanism of radiation damage formation remain largely unanswered. Among all biomolecules exposed to radiation, DNA plays an important role because any damage to its molecular structure can affect the whole cell and may lead to chromosomal rearrangements resulting in genomic instability or cell death. To identify and characterize damage induced in the DNA sugar-phosphate backbone, in this work we performed x-ray absorption spectroscopy at the P K-edge on DNA irradiated with either UVA light or protons. By combining the experimental results with theoretical calculations, we were able to establish the types and relative ratio of lesions produced by both UVA and protons around the phosphorus atoms in DNA. 相似文献
44.
Agnieszka Kolacinska Jan Morawiec Wojciech Fendler Beata Malachowska Zbigniew Morawiec Janusz Szemraj Zofia Pawlowska Dipanjan Chowdhury Young Eun Choi Robert Kubiak Lukasz Pakula Izabela Zawlik 《Molecular biology reports》2014,41(5):2851-2857
Triple negative breast cancer (TNBC) has caught the attention of oncologists worldwide because of poor prognosis and paucity of targeted therapies. Gene pathways have been widely studied, but less is known about epigenetic factors such as microRNAs (miRNAs) and their role in tailoring an individual systemic and surgical approach for breast cancer patients. The aim of the study was to examine selected miRNAs in TNBC core biopsies sampled before preoperative chemotherapy and the subsequent pathologic response in mastectomy or breast conservation specimens. Prior to treatment, core needle biopsies were collected from 11 female patients with inoperable locally advanced TNBC or large resectable tumors suitable for down-staging. In all 11 TNBC core biopsies we analyzed 19 miRNAs per sample: 512, 190, 200, 346, 148, 449, 203, 577, 93, 126, 423, 129, 193, 182, 136, 135, 191, 122 and 222 (miRCURY LNA? Universal RT microRNA polymerase chain reaction Custom Pick & Mixpanels). The Wilcoxon signed-rank test was used to compare related samples. Ingenuity pathway analysis was used to evaluate potential functional significance of differentially expressed miRNAs. Statistical analysis showed that 3 of 19 miRNAs differed in relation to pathologic response i.e. good versus poor. These differences failed to reach statistical significance, although a trend was observed (p = 0.06). Among these miRNAs, we identified—miR-200b-3p, miR-190a and miR-512-5p. In summary, our results indicate that higher miR-200b-3p, higher miR-190a and lower miR-512-5p expression levels in core biopsies sampled from TNBC patients may be associated with better pathologic response to chemotherapy and the increased feasibility of breast conserving surgery in these patients. Although these results were from a small cohort, they provide an important basis for larger, prospective, multicenter studies to investigate the potential role of miRNAs in neoadjuvant setting. 相似文献
45.
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
46.
Anna Kobylańska Elżbieta Pluskota Zofia Pawtowska Andrzej Okruszek Czeslaw S. Cierniewski Wojciech J. Stec 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1709-1710
Abstract The cytotoxicity of anti-PAI-5 hexadecanucleotides (phosphodiesters and phosphorothioates) and their conjugates with lipophilic alcohols was tested in EA.hy 926 hybrid endothelial cells. Some cytotoxicity was found for cholesteryl and bornyl conjugates at concentrations higher than those used for antisense inhibition experiments. 相似文献
47.
Abstract Using the Weeks-Chandler-Andersen separation of the intermolecular potential we have fitted computer simulation data for Lennard-Jones system for the whole phase plane to the same form expression but in two different ways: locally and globally. We compare the efficacy and the exactness of both methods. 相似文献
48.
49.
Comparative analysis of the receptor-like kinase family in Arabidopsis and rice 总被引:24,自引:0,他引:24 下载免费PDF全文
Receptor-like kinases (RLKs) belong to the large RLK/Pelle gene family, and it is known that the Arabidopsis thaliana genome contains >600 such members, which play important roles in plant growth, development, and defense responses. Surprisingly, we found that rice (Oryza sativa) has nearly twice as many RLK/Pelle members as Arabidopsis does, and it is not simply a consequence of a larger predicted gene number in rice. From the inferred phylogeny of all Arabidopsis and rice RLK/Pelle members, we estimated that the common ancestor of Arabidopsis and rice had >440 RLK/Pelles and that large-scale expansions of certain RLK/Pelle members and fusions of novel domains have occurred in both the Arabidopsis and rice lineages since their divergence. In addition, the extracellular domains have higher nonsynonymous substitution rates than the intracellular domains, consistent with the role of extracellular domains in sensing diverse signals. The lineage-specific expansions in Arabidopsis can be attributed to both tandem and large-scale duplications, whereas tandem duplication seems to be the major mechanism for recent expansions in rice. Interestingly, although the RLKs that are involved in development seem to have rarely been duplicated after the Arabidopsis-rice split, those that are involved in defense/disease resistance apparently have undergone many duplication events. These findings led us to hypothesize that most of the recent expansions of the RLK/Pelle family have involved defense/resistance-related genes. 相似文献
50.
Wojciech Galinski 《Trees - Structure and Function》1994,8(3):160-164
Summary Two experiments were performed to test needle architecture of Scots pine (Pinus sylvestris L.) seedlings when affected by non-shading neighbouring vegetation. Both experiments showed that seedlings reacted to the presence of such adjacent vegetation by changes in needle distribution around the main stem: more needles were found on the opposite side of the main stem to where the vegetation was located. However, this reaction was confined to needles from the main stem. Responses of seedlings to dead neighbours differed from the response to live neighbours and also from the response to a black curtain substituted for plant neighbours. It is suggested that reactions are mediated by the red/far red ratio of incident light. 相似文献