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11.
Said Akli Xin-Qiao Zhang Jolanta Bondaruk Susan L Tucker P. Bogdan Czerniak William F Benedict Khandan Keyomarsi 《Cell cycle (Georgetown, Tex.)》2012,11(7):1468-1476
Expression of low molecular weight (LMW) isoforms of cyclin E is a strong predictor of poor outcome in patients with breast cancer. The purpose of this study was to examine the expression of full-length and LMW cyclin E in bladder cancer cell lines and patient tumors. We used western blotting, immunoprecipitation and kinase assays to examine the expression and activity of key cell cycle-regulatory proteins in various human bladder cell lines, both tumorigenic and non-tumorigenic. We also analyzed cyclin E expression, kinase activity and immune complex binding partners in 43 tissue samples from grade 2 and 3 transitional cell carcinomas. Cyclin E was overexpressed and LMW isoforms were present only in bladder cancer cells. Overexpression of LMW isoforms of cyclin E and increased cyclin E kinase activity were both significantly associated with tumorigenicity of the bladder cell lines (p = 0.005 and 0.022, respectively). Binding of the cyclin-dependent kinase inhibitors p21 and p27 to LMW cyclin E did not inhibit the kinase activity of cyclin E and cyclin-dependent kinase 2 in primary tumor samples overexpressing LMW cyclin E. Full-length and LMW cyclin E were significantly overexpressed in grade 3 tumors compared with grade 2 tumors (p = 0.004). Finally, LMW cyclin E levels were significantly associated with a non-papillary growth pattern (p = 0.031) and invasiveness (p = 0.021) of the bladder tumors and poor overall survival (p = 0.06). These results suggest that LMW cyclin E can be used as a new prognostic marker for bladder cancer.Key words: cyclin E, p27, Cdk2 kinase, bladder cancer, cell cycle 相似文献
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Physiological and antioxidant responses of two accessions of Arabidopsis thaliana in different light and temperature conditions 下载免费PDF全文
Renata Szymańska Beatrycze Nowicka Michał Gabruk Sława Glińska Sylwia Michlewska Jolanta Dłużewska Anna Sawicka Jerzy Kruk Roosa Laitinen 《Physiologia plantarum》2015,154(2):194-209
During their lifetime, plants need to adapt to a changing environment, including light and temperature. To understand how these factors influence plant growth, we investigated the physiological and antioxidant responses of two Arabidopsis accessions, Shahdara (Sha) from the Shahdara valley (Tajikistan, Central Asia) in a mountainous area and Lovvik‐5 (Lov‐5) from northern Sweden to different light and temperature conditions. These accessions originate from different latitudes and have different life strategies, both of which are known to be influenced by light and temperature. We showed that both accessions grew better in high‐light and at a lower temperature (16°C) than in low light and at 23°C. Interestingly, Sha had a lower chlorophyll content but more efficient non‐photochemical quenching than Lov‐5. Sha, also showed a higher expression of vitamin E biosynthetic genes. We did not observe any difference in the antioxidant prenyllipid level under these conditions. Our results suggest that the mechanisms that keep the plastoquinone (PQ)‐pool in more oxidized state could play a role in the adaptation of these accessions to their local climatic conditions. 相似文献
14.
Due to the variant functions that estrogens play in the regulation of reproduction, development of the mammary gland, growth
and differentiation of cells, estrogen receptors and their genes are considered as a candidates for the markers of production
and functional traits in farm animals, including cattle. In the earliest study, a 2853-bp bovine ER gene 5′-region was PCR
amplified and sequenced. Moreover, for the first time, a polymorphism was described within 5′ region of the bovine ERα gene—A/G
transition lying upstream at position 2591 from acceptor splice site +85, possibly within its promoter—which could be recognized
with RFLP-BglI. In other study we are found second polymorphism—A/G transition at position 1213 from acceptor splice site +85, located
in promoter for exon B. We have examined the specific mRNA expression of ERα in various genotypes using real-time RT-PCR.
We used four animals from each genotype group—AG, GG for BglI and AA, AG for SnaBI—to analyse liver ERα expression at the level of Real-time PCR. Liver samples were taken from the 16 young Friesian bulls
of the different ERα genotypes, slaughtered at the local abattoir. As shown by Real-Time PCR, on the livers of animals with
different genotype ERα mRNA for BglI polymorphism we didn’t found variability, but for SnaBI we have found variability between AG and AA genotypes. 相似文献
15.
Kozielec T Pózniak J Salacka A Hornowska I Kotkowiak L 《Biological trace element research》2003,93(1-3):47-53
The aim of this study was to assess the hair copper concentration in a population of healthy children, teenagers, and adults
living in a specific region of Poland. For this purpose, 840 healthy individuals aged 1–50 yr living in Szczecin, Poland were
selected for the study. They were divided into subgroups according to age and sex and the hair was analyzed for copper using
a standard atomic absorption spectrometric technique. The level of copper was highest for the group including 11–15 yr old.
In the other subgroups, the concentration of copper was lower than the values considered normal, suggesting the possibility
of endemic copper deficiency in the inhabitants of this region. 相似文献
16.
The diploid number 2n = 46 and the chromosome arm number NF = 74 are described in Lithobius forficatus from Olsztyn (Poland). Analyses of silver and CMA3-stained mitotic chromosomes suggest that a single chromosome pair has active NORs which correspond to G-C-rich (CMA3-positive) chromatin. Heteromorphism of the largest metacentric chromosome pair was observed. The sex chromosomes were not identified. Size polymorphism of the first chromosome pair was found. 相似文献
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18.
Zawilak-Pawlik AM Kois A Zakrzewska-Czerwinska J 《Protein expression and purification》2006,48(1):126-133
An improved, simplified method for the purification of recombinant, tagged DnaA proteins is described. The presented protocol allowed us to purify soluble DnaA proteins from two different bacterial species: Helicobacter pylori and Streptomyces coelicolor, but it can most likely also be used for the isolation of DnaA proteins from other bacteria, as it was adapted for Mycobacterium tuberculosis DnaA. The isolation procedure consists of protein precipitation with ammonium sulphate followed by affinity chromatography. The composition of the buffers used at each purification step is crucial for the successful isolation of the recombinant DnaA proteins. The universality of the method in terms of its application to differently tagged proteins (His-tagged or GST-tagged) as well as different properties of purified proteins (e.g., highly aggregating truncated forms) makes the protocol highly useful for all studies requiring purified and active DnaA proteins. 相似文献
19.
Adrian Doroszko Thomas S Hurst Dorota Polewicz Jolanta Sawicka Justyna Fert-Bober David H Johnson Grzegorz Sawicki 《Proteome science》2010,8(1):3
Background
Although mechanical ventilation (MV) is a major supportive therapy for patients with acute respiratory distress syndrome, it may result in side effects including lung injury. In this study we hypothesize that MMP-9 inhibition by doxycycline might reduce MV-related lung damage. Using a proteomic approach we identified the pulmonary proteins altered in high volume ventilation-induced lung injury (VILI). Forty Wistar rats were randomized to an orally pretreated with doxycycline group (n = 20) or to a placebo group (n = 20) each of which was followed by instrumentation prior to either low or high tidal volume mechanical ventilation. Afterwards, animals were euthanized and lungs were harvested for subsequent analyses. 相似文献20.
Summary The nervous system of the most primitive fresh-water Turbellaria of the order Catenulida was investigated. Neurosecretory
cells were found to occur in it. These cells have a structure similar to that of nerve cells, they only differ by the presence
of neurosecretion granules and a more developed golgi complex. In the simplest Catenulida,Stenostomun, neurosecretory granules are found both in the brain cells and in the trunks in the nerve fibres where they are rather randomly
distributed. Another representative of this family, the more highly organizedCatenula, exhibits specialized brain and nerve trunk regions containing neurosecretion granules.
This work was supported in part by the Committee on Cytobiology of the Polish Academy of Sciences 相似文献