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381.
Waldemar Kiszczak Dorota Krzyżanowska Krystyna Strycharczuk Urszula Kowalska Bogdan Wolko Krystyna Górecka 《Acta Physiologiae Plantarum》2011,33(2):401-407
The purpose of the present work was to evaluate carrot plants obtained from anther cultures with respect to their ploidy and
homozygosity. Ploidy was determined using flow cytometry. Homozygosity of analyzed plants was determined using isoenzymes,
glucose-6-phosphate isomerase (PGI) and aspartate aminotransferase (AAT). The cytometric tests revealed that more than 90%
of the carrot plants obtained from anther cultures were doubled haploid. In the initial assessment of polymorphism of the
two enzymatic systems in selected androgenetic carrot plants of the cultivars: Berjo, Kazan F1, and Splendid F1, it was proven that 100% of those plants were homozygotes in respect to PGI and also with respect to AAT. In the second experiment,
the obtained androgenetic progeny of the heterozygous donor plant of cultivar Narbonne F1 was found to be 94% homozygotic with respect to PGI and 100% homozygotic in the case of AAT. For the androgenetic plants
of the cultivar Kazan F1, 89% of them were homozygotic with respect to AAT but PGI enzyme system did not differentiate the homozygotic and heterozygotic
androgenetic progeny. These results indicated that enzyme polymorphism depends on carrot genotype, therefore, analysis of
some (more than one) isozymes was necessary to confirm homozygosity of plants. PGI and AAT can be a useful tool for determining
homozygosity in androgenetic carrot plants. 相似文献
382.
Cardiomyocytes have multiple Ca(2+) fluxes of varying duration that work together to optimize function (1,2). Changes in Ca(2+) activity in response to extracellular agents is predominantly regulated by the phospholipase Cβ- Gα(q;) pathway localized on the plasma membrane which is stimulated by agents such as acetylcholine (3,4). We have recently found that plasma membrane protein domains called caveolae(5,6) can entrap activated Gα(q;)(7). This entrapment has the effect of stabilizing the activated state of Gα(q;) and resulting in prolonged Ca(2+) signals in cardiomyocytes and other cell types(8). We uncovered this surprising result by measuring dynamic calcium responses on a fast scale in living cardiomyocytes. Briefly, cells are loaded with a fluorescent Ca(2+) indicator. In our studies, we used Ca(2+) Green (Invitrogen, Inc.) which exhibits an increase in fluorescence emission intensity upon binding of calcium ions. The fluorescence intensity is then recorded for using a line-scan mode of a laser scanning confocal microscope. This method allows rapid acquisition of the time course of fluorescence intensity in pixels along a selected line, producing several hundreds of time traces on the microsecond time scale. These very fast traces are transferred into excel and then into Sigmaplot for analysis, and are compared to traces obtained for electronic noise, free dye, and other controls. To dissect Ca(2+) responses of different flux rates, we performed a histogram analysis that binned pixel intensities with time. Binning allows us to group over 500 traces of scans and visualize the compiled results spatially and temporally on a single plot. Thus, the slow Ca(2+) waves that are difficult to discern when the scans are overlaid due to different peak placement and noise, can be readily seen in the binned histograms. Very fast fluxes in the time scale of the measurement show a narrow distribution of intensities in the very short time bins whereas longer Ca(2+) waves show binned data with a broad distribution over longer time bins. These different time distributions allow us to dissect the timing of Ca(2+)fluxes in the cells, and to determine their impact on various cellular events. 相似文献
383.
Carcinomas are complex tissues comprised of neoplastic cells and a non-cancerous compartment referred to as the 'stroma'. The stroma consists of extracellular matrix (ECM) and a variety of mesenchymal cells, including fibroblasts, myofibroblasts, endothelial cells, pericytes and leukocytes (1-3). The tumour-associated stroma is responsive to substantial paracrine signals released by neighbouring carcinoma cells. During the disease process, the stroma often becomes populated by carcinoma-associated fibroblasts (CAFs) including large numbers of myofibroblasts. These cells have previously been extracted from many different types of human carcinomas for their in vitro culture. A subpopulation of CAFs is distinguishable through their up-regulation of α-smooth muscle actin (α-SMA) expression(4,5). These cells are a hallmark of 'activated fibroblasts' that share similar properties with myofibroblasts commonly observed in injured and fibrotic tissues (6). The presence of this myofibroblastic CAF subset is highly related to high-grade malignancies and associated with poor prognoses in patients. Many laboratories, including our own, have shown that CAFs, when injected with carcinoma cells into immunodeficient mice, are capable of substantially promoting tumourigenesis (7-10). CAFs prepared from carcinoma patients, however, frequently undergo senescence during propagation in culture limiting the extensiveness of their use throughout ongoing experimentation. To overcome this difficulty, we developed a novel technique to experimentally generate immortalised human mammary CAF cell lines (exp-CAFs) from human mammary fibroblasts, using a coimplantation breast tumour xenograft model. In order to generate exp-CAFs, parental human mammary fibroblasts, obtained from the reduction mammoplasty tissue, were first immortalised with hTERT, the catalytic subunit of the telomerase holoenzyme, and engineered to express GFP and a puromycin resistance gene. These cells were coimplanted with MCF-7 human breast carcinoma cells expressing an activated ras oncogene (MCF-7-ras cells) into a mouse xenograft. After a period of incubation in vivo, the initially injected human mammary fibroblasts were extracted from the tumour xenografts on the basis of their puromycin resistance (11). We observed that the resident human mammary fibroblasts have differentiated, adopting a myofibroblastic phenotype and acquired tumour-promoting properties during the course of tumour progression. Importantly, these cells, defined as exp-CAFs, closely mimic the tumour-promoting myofibroblastic phenotype of CAFs isolated from breast carcinomas dissected from patients. Our tumour xenograft-derived exp-CAFs therefore provide an effective model to study the biology of CAFs in human breast carcinomas. The described protocol may also be extended for generating and characterising various CAF populations derived from other types of human carcinomas. 相似文献
384.
Marta Okniska Bouchra El‐Hafny‐Rahbi Aleksandra Paterek Urszula Mackiewicz Claire Crola‐Da Silva Klaudia Brodaczewska Micha Mczewski Claudine Kieda 《Journal of cellular and molecular medicine》2020,24(3):2272-2283
Heart failure is a consequence of progression hypoxia‐dependent tissue damages. Therapeutic approaches to restore and/or protect the healthy cardiac tissue have largely failed and remain a major challenge of regenerative medicine. The myo‐inositol trispyrophosphate (ITPP) is a modifier of haemoglobin which enters the red blood cells and modifies the haemoglobin properties, allowing for easier and better delivery of oxygen by the blood. Here, we show that this treatment approach in an in vivo model of myocardial infarction (MI) results in an efficient protection from heart failure, and we demonstrate the recovery effect on post‐MI left ventricular remodelling in the rat model. Cultured cardiomyocytes used to study the molecular mechanism of action of ITPP in vitro displayed the fast stimulation of HIF‐1 upon hypoxic conditions. HIF‐1 overexpression was prevented by ITPP when incorporated into red blood cells applied in a model of blood‐perfused cardiomyocytes coupling the dynamic shear stress effect to the enhanced O2 supply by modification of haemoglobin ability to release O2 in hypoxia. ITPP treatment appears a breakthrough strategy for the efficient and safe treatment of hypoxia‐ or ischaemia‐induced injury of cardiac tissue. 相似文献
385.
Yannick Simonin Serena Vegna Leila Akkari Damien Grégoire Etienne Antoine Jacques Piette Nicolas Floc'h Patrice Lassus Guann-Yi Yu Arielle R. Rosenberg Michael Karin David Durantel Urszula Hibner 《PLoS pathogens》2013,9(3)
Exposure to hepatitis C virus (HCV) typically results in chronic infection that leads to progressive liver disease ranging from mild inflammation to severe fibrosis and cirrhosis as well as primary liver cancer. HCV triggers innate immune signaling within the infected hepatocyte, a first step in mounting of the adaptive response against HCV infection. Persistent inflammation is strongly associated with liver tumorigenesis. The goal of our work was to investigate the initiation of the inflammatory processes triggered by HCV viral proteins in their host cell and their possible link with HCV-related liver cancer. We report a dramatic upregulation of the lymphotoxin signaling pathway and more specifically of lymphotoxin-β in tumors of the FL-N/35 HCV-transgenic mice. Lymphotoxin expression is accompanied by activation of NF-κB, neosynthesis of chemokines and intra-tumoral recruitment of mononuclear cells. Spectacularly, IKKβ inactivation in FL-N/35 mice drastically reduces tumor incidence. Activation of lymphotoxin-β pathway can be reproduced in several cellular models, including the full length replicon and HCV-infected primary human hepatocytes. We have identified NS5B, the HCV RNA dependent RNA polymerase, as the viral protein responsible for this phenotype and shown that pharmacological inhibition of its activity alleviates activation of the pro-inflammatory pathway. These results open new perspectives in understanding the inflammatory mechanisms linked to HCV infection and tumorigenesis. 相似文献
386.
387.
Cancerous stroma coevolves alongside tumour progression, thereby promoting the malignant conversion of epithelial carcinoma cells. To date, an abundance of data have supported crucial roles of the tumour microenvironment (TME) in providing cancer cells with proliferative, migratory, survival and invasive propensities favouring the processes of tumourigenesis. The cancerous reactive stroma is frequently populated by a large number of myofibroblasts (MFs), which are activated, non‐transformed fibroblasts expressing α‐smooth muscle actin (α‐SMA). MFs together with non‐MF cells present in the tumour‐associated stroma are collectively referred to as carcinoma‐associated fibroblasts (CAFs), one of the major stromal cell types recognised in various human carcinomas. Recruitment of fibroblasts and/or their progenitors to a tumour mass and their subsequent transdifferentiation into MFs, as well as ongoing maintenance of their activated state, are believed to be essential processes facilitating tumour progression. However, the complex networks of signalling pathways mediating the phenotypic conversion into CAFs, as well as those underlying their tumour‐promoting interactions with other tumour‐constituting cells, have yet to be fully explored. Histopathological confirmation of the presence of large numbers of CAF MFs within TME and their altered gene expression profiles are known to be associated with disease progression and to serve as independent negative prognostic factors for a wide range of tumour types. In this review, we examine the current evidence shedding light on the emerging roles of tumour‐promoting CAFs, cells that are pivotal for epithelial cancer development and progression, and discuss the therapeutic potential of targeting these cells. J. Cell. Physiol. 228: 1651–1657, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
388.
Karolina Dębska Urszula KrasuskaKatarzyna Budnicka Renata BogatekAgnieszka Gniazdowska 《Journal of plant physiology》2013
Reactive oxygen (ROS) and nitrogen (RNS) species play a signaling role in seed dormancy alleviation and germination. Their action may be described by the oxidative/nitrosative “window/door”. ROS accumulation in embryos could lead to oxidative modification of protein through carbonylation. Mature apple (Malus domestica Borkh.) seeds are dormant and do not germinate. Their dormancy may be overcome by 70–90 days long cold stratification. The aim of this work was to analyze the relationship between germinability of embryos isolated from cold (5 °C) or warm (25 °C) stratified apple seeds and ROS or nitric oxide (NO) production and accumulation of protein carbonyl groups. A biphasic pattern of variation in H2O2 concentration in the embryos during cold stratification was detected. H2O2 content increased markedly after 7 days of seeds imbibition at 5 °C. After an additional two months of cold stratification, the H2O2 concentration in embryos reached the maximum. NO production by the embryos was low during entire period of stratification, but increased significantly in germination sensu stricto (i.e. phase II of the germination process). The highest content of protein carbonyl groups was detected after 6 weeks of cold stratification treatment. Fluctuation of H2O2 and protein carbonylation seems to play a pivotal role in seed dormancy alleviation by cold stratification, while NO appears to be necessary for seed germination. 相似文献
389.
Urszula Mazurek Magdalena C. Kimsa Barbara Strzalka-Mrozik Malgorzata W. Kimsa Jolanta Adamska Daniel Lipinski Joanna Zeyland Marlena Szalata Ryszard Slomski Jacek Jura Zdzislaw Smorag Roman Nowak Joanna Gola 《Current microbiology》2013,67(4):505-514
The pig appears to be the most promising animal donor of organs for use in human recipients. Among several types of pathogens found in pigs, one of the greatest problems is presented by porcine endogenous retroviruses (PERVs). Screening of the source pig herd for PERVs should include analysis of both PERV DNA and RNA. Therefore, the present study focuses on quantitative analysis of PERVs in different organs such as the skin, heart, muscle, and liver and blood of transgenic pigs generated for xenotransplantation. Transgenic pigs were developed to express the human α-galactosidase, the human α-1,2-fucosyltransferase gene, or both genetic modifications of the genome (Lipinski et al., Medycyna Wet 66:316–322, 2010; Lipinski et al., Ann Anim Sci 12:349–356, 2012; Wieczorek et al., Medycyna Wet 67:462–466, 2011). The copy numbers of PERV DNA and RNA were evaluated using real-time Q-PCR and QRT-PCR, respectively. Comparative analysis of all PERV subtypes revealed the following relationships: PERV A > PERV B > PERV C. PERV A and B were found in all samples, whereas PERV C was detected in 47 % of the tested animals. The lowest level of PERV DNA was shown in the muscles for PERV A and B and in blood samples for PERV C. The lowest level of PERV A RNA was found in the skin, whereas those of PERV B and C RNA were found in liver specimens. Quantitative analysis revealed differences in the copy number of PERV subtypes between various organs of transgenic pigs generated for xenotransplantation. Our data support the idea that careful pig selection for organ donation with low PERV copy number may limit the risk of retrovirus transmission to the human recipients. 相似文献
390.
Alicja?Piotrowska-NiczyporukEmail authorView authors OrcID profile Andrzej?Bajguz Urszula?Kotowska Monika?Bralska Marta?Talarek-Karwel 《Journal of Plant Growth Regulation》2018,37(4):1159-1174
The effects of auxins and cytokinins at the range of concentrations 0.0001–100 µM on Acutodesmus obliquus (Chlorophyceae) cultures were studied. Microalga exhibited sensitivity to cytokinins in the following order: 0.01 µM tZ?>?0.1 µM Kin?>?1 µM DPU, whereas the hierarchy of auxin activity was: 0.01 µM IAA?>?0.1 µM IBA?>?0.1 µM PAA. Cytokinins possessed higher stimulating properties on the cell number, whereas auxins increased the size of cells. Differences in the metabolite profiles of the cultures treated with phytohormones were observed. Auxins and cytokinins had a positive effect on the photosynthetic apparatus enhancing the level of chlorophylls, carotenes, and xanthophylls. In comparison with auxins, cytokinins more effectively delayed oxidative damage by increasing the level of non-enzymatic antioxidants (ascorbate, glutathione) and the activity of enzymes scavenging reactive oxidative species (catalase, glutathione reductase, ascorbate peroxidase). On the other hand, auxins stimulated superoxide dismutase activity and provoked hydrogen peroxide generation, which may be involved in cell enlargement. All phytohormones reduced the content of abscisic acid and controlled the level of endogenous auxin and cytokinins suggesting complex interactions. Different dynamics of A. obliquus responses to auxins and cytokinins clearly demonstrated their diverse roles in algal growth and metabolism. 相似文献