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121.
Jacek?Siciński Krzysztof?PabisEmail author Krzysztof?Ja?d?ewski Alicja?Konopacka Magdalena?B?a?ewicz-Paszkowycz 《Polar Biology》2012,35(3):355-367
There are only few studies on shallow Antarctic benthic communities associated with habitats affected by intense mineral sedimentation
inflow. The analysis of macrofaunal communities associated with two shallow, isolated glacial coves was performed in Admiralty
Bay (King George Island) and compared with non-disturbed sites. Multivariate analyses (hierarchical classification, nMDS)
clearly separated glacial cove communities (two assemblages) from the sites situated outside both basins (two assemblages).
The community influenced by the streamflow of glacial discharge of meltwater situated in the area with sandy–clay–silt sediments
had a very low species richness, diversity and abundance. It was dominated by eurytopic, motile deposit feeding polychaetes
such as Mesospio
moorei, Tharyx
cincinnatus and Leitoscoloplos
kerguelensis as well as the bivalve Yoldia
eightsi. The second glacial community of the area located at a grater distance from the outlet of the stream was characterized by
sandy–clay–silt and clay–silt deposits and showed also a low diversity and species richness. The most abundant here were peracarid
crustaceans, with the dominant opportunistic feeder Cheirimedon
femoratus. Community from the non-disturbed area with silty–clay–sand, and silty–sand sediments had higher species richness and diversity.
The assemblage of fauna from the sandy bottom has values of those two indexes similar to those found in the disturbed areas. 相似文献
122.
Enthoprotin: a novel clathrin-associated protein identified through subcellular proteomics 总被引:19,自引:0,他引:19
Wasiak S Legendre-Guillemin V Puertollano R Blondeau F Girard M de Heuvel E Boismenu D Bell AW Bonifacino JS McPherson PS 《The Journal of cell biology》2002,158(5):855-862
Despite numerous advances in the identification of the molecular machinery for clathrin-mediated budding at the plasma membrane, the mechanistic details of this process remain incomplete. Moreover, relatively little is known regarding the regulation of clathrin-mediated budding at other membrane systems. To address these issues, we have utilized the powerful new approach of subcellular proteomics to identify novel proteins present on highly enriched clathrin-coated vesicles (CCVs). Among the ten novel proteins identified is the rat homologue of a predicted gene product from human, mouse, and Drosophila genomics projects, which we named enthoprotin. Enthoprotin is highly enriched on CCVs isolated from rat brain and liver extracts. In cells, enthoprotin demonstrates a punctate staining pattern that is concentrated in a perinuclear compartment where it colocalizes with clathrin and the clathrin adaptor protein (AP)1. Enthoprotin interacts with the clathrin adaptors AP1 and with Golgi-localized, gamma-ear-containing, Arf-binding protein 2. Through its COOH-terminal domain, enthoprotin binds to the terminal domain of the clathrin heavy chain and stimulates clathrin assembly. These data suggest a role for enthoprotin in clathrin-mediated budding on internal membranes. Our study reveals the utility of proteomics in the identification of novel vesicle trafficking proteins. 相似文献
123.
Ewelina Wawryk-Gawda Patrycja Chylińska-Wrzos Marta Lis-Sochocka Katarzyna Chłapek Kamila Bulak Marian Jędrych Barbara Jodłowska-Jędrych 《Protoplasma》2014,251(3):525-533
The p53 protein is an important factor of many intra- and extracellular processes. This protein regulates the repair of cellular DNA and induces apoptosis. It is also responsible for the regulation of the senescence and the cell entering the subsequent stages of the cellular cycle. The protein p53 is also involved in inhibiting angiogenesis and the induction of oxidative shock. In our study, we examined the activity of p53 protein in the uterine epithelial cells in rats treated with cladribine. Its action is mainly based on apoptosis induction. We compared the activity of p53 protein in cells with a high apoptosis index and in cells with active repair mechanisms and high proliferation index. We observed stronger p53 protein expression in the epithelial cells of the materials taken 24 h after the last dose of 2-CdA associated with the active process of apoptosis and inhibition of proliferation. After 4 weeks from the last dose of cladribine, the stronger expression of p53 protein was associated with both the existing changes in the cell's genome, the effects of the ongoing repair mechanisms, as well as the high proliferation activity. 相似文献
124.
Kozłowski M Naumnik W Nikliński J Milewski R Lapuć G Laudański J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):90-97
The discovery of markers to lymphatic endothelial cells and the development of novel antibodies to these markers have brought increasing attention to the lymphatics and progress in the understanding of lymphangiogenesis and cancer metastasis. In this study, we investigate the presence of lymphatic vessel invasion (LVI) detected by D2-40 immunohistochemical staining in resected esophageal cancer and correlated with clinicopathologic data and patient survival. Sixty nine patients, who had a primary resection of esophageal cancer, were analyzed by univariate and multivariate logistic regression, and univariate and multivariate survival analysis. The total rate of LVI was 72% (50/69). Positive LVI was significantly correlated with lymph node metastasis (p < 0.001), tumor size (p < 0.001), histological grading (p = 0.017), tumor depth (p = 0.001), and stage (p < 0.001). Multivariate logistic analysis identified LVI (p = 0.036) as a predictor of regional lymph node metastasis. On univariate survival analysis, patients with LVI had a significantly shorter disease-free survival, cancer-specific survival and overall survival. Multivariate analysis proved that LVI diagnosed by D2-40 is an independent prognostic factor of both disease-free survival (p = 0.04) and overall survival (p = 0.032) in resected esophageal cancer. These results show that LVI assessment identifies patients at high risk for regional lymph node metastasis and that LVI is an independent prognostic factor in patients with esophageal cancer. 相似文献
125.
Lubiński J Górski B Kurzawski G Jakubowska A Cybulski C Suchy J Debniak T Grabowska E Lener M Nej K 《Acta biochimica Polonica》2002,49(3):571-581
On the basis of literature data and own experience the authors review the current knowledge about the molecular basis of inherited predispositions for tumors. They hypothesize that in the near perspective 5-10 years studies using existing registry data/material and the latest novel technology will allow the identification of the molecular background for the majority of hereditary cancers which will have enormous practical consequences especially for the prevention of malignancies. 相似文献
126.
Dolińska B Caban A Leszczyńska L Oczkowicz G Ryszka F 《Protein and peptide letters》2011,18(6):540-544
The prolactin (PRL) permeation through the pericardium depending on the species of origin (porcine, bovine and ovine) was studied, and the parameters of its bioavailability were calculated. An in vitro model using pericardium as a natural membrane and Frantz cell method was applied. Significant differences in permeation were observed depending on the species of origin. Within 5 h, 17.5% of bovine PRL, 27.2% of porcine PRL and 90.3% of ovine PRL permeated the pericardium. The amount of permeated ovine PRL was 3.3-fold higher than porcine PRL and 5.2-fold higher than bovine PRL. The maximum concentration of permeated PRL was reached in the thirtieth minute of the experiment and was the highest for ovine PRL (C(max) = 677.21 μg/cm2) and the lowest for bovine PRL (C(max) = 259.97 μg/cm2). Bioavailability of PRL through the pericardium is 3.3-fold greater for ovine PRL in comparison to porcine or bovine PRL. The relative extent of bioavailability for bovine and ovine prolactin versus the porcine PRL standard was 85.6% and 229.3%, respectively. 相似文献
127.
Marta Spodzieja Monika Rafalik Aneta Szymańska Aleksandra S. Kołodziejczyk Paulina Czaplewska 《Journal of molecular recognition : JMR》2013,26(9):415-425
Secondary amyloid A (AA) amyloidosis is an important complication of some chronic inflammatory diseases, primarily rheumatoid arthritis (RA). It is a serious, potentially life‐threatening disorder caused by the deposition of AA fibrils, which are derived from the circulatory, acute‐phase‐reactant, serum amyloid A protein (SAA). Recently, a specific interaction between SAA and the ubiquitous inhibitor of cysteine proteases—human cystatin C (hCC)—has been proved. Using a combination of selective proteolytic excision and high‐resolution mass spectrometry, the binding sites in the SAA and hCC sequences were assessed as SAA(86–104) and hCC(96–102), respectively. Here, we report further details concerning the hCC–SAA interaction. With the use of affinity tests and florescent ELISA‐like assays, the amino acid residues crucial for the protein interaction were determined. It was shown that all amino acid residues in the SAA sequence, essential for the formation of the protein complex, are basic ones, which suggests an electrostatic interaction character. The idea is corroborated by the fact that the most important residues in the hCC sequence are Ser‐98 and Tyr‐102; these residues are able to form hydrogen bonds via their hydroxyl groups. The molecular details of hCC–SAA complex formation might be helpful for the design of new compounds modulating the biological role of both proteins. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
128.
Testicular morphology and expression of aromatase in testes of mice with the mosaic mutation (Atp7a mo-ms) 总被引:1,自引:0,他引:1
The aim of this study was to determine whether testicular cells of mice with the mosaic mutation, associated with abnormal copper metabolism, are able to aromatize androgens to estrogens, and what is the putative role of estrogens in the gonad of the mutant male. Mosaic is a lethal mutation; affected males usually die on about day 16. Those, which survive to reach sexual maturity, are valuable research subjects. In testes of young and adult mutants, histological analysis revealed the presence of many degenerating seminiferous tubules besides normal-looking ones. Additionally, high numbers of apoptotic germ cells were observed, especially in young mutants when compared with the controls. Positive immunostaining for aromatase was found in cultured Leydig cells and testicular sections of both control and mutant males. The intensity of immunostaining was always stronger in the mosaic mice. In both groups, Western-blot analysis revealed the presence of aromatase protein as a single band of approximately 55 kDa. In the mosaic males, levels of testosterone in cultured Leydig cells, whole testes, and in blood plasma were lower than in those of the respective controls. On the contrary, estradiol concentrations were always higher in the mutants. Both in vivo and in vitro studies indicate that morphological and functional changes in the testes of the mosaic mice mainly result from defective copper metabolism. The higher level of endogenous estrogens can additionally enhance morphological alterations within the testes. It seems also likely that excess estrogens may affect the survival rate of the mosaic males. 相似文献
129.
Magdalena Semla Pavol Schwarcz Ján Mezey Łukasz J. Binkowski Martyna Błaszczyk Grzegorz Formicki Agnieszka Greń Robert Stawarz Peter Massanyi 《Biological trace element research》2018,184(1):33-41
Wine consumption delivers macroelements and microelements necessary for the proper metabolism. On the other hand, wine can be an important source of toxic metals. The aim of this study was to estimate the concentrations of Ca, Cd, Cu, Fe, Hg, Mg, Ni, Pb, and Zn in the Slovak and non-Slovak wines. The concentration of metals was evaluated with respect to the type, the alcohol content, and the age of Slovak wine. The general scheme of concentrations found was as follows Ca > Mg > Fe > Zn > Pb > Cd > Ni > Cu > Hg. The type of wine and the alcohol content do not have a significant impact on metal concentrations. Also, the age of wine has no influence on the mean concentration of metals, except for Zn. Metal concentrations in Slovak and non-Slovak wines indicate similar contents of metals, except for Ni. The contribution to both dietary reference values (DRVs) and provisional tolerable weekly intake (PTWI) evaluations in the Slovak wine suggested low dietary exposure to Ca, Cu, Fe, Mg, Ni, Zn, Cd, Hg, and Pb, respectively. However, we do not suggest that the consumption of all Slovak wines is healthy. The maximum Pb concentrations in Slovak wines exceed the maximum permitted level proposed by the European Commission. This might be proved by the results of the margin of the exposure (MOE) value evaluation in the samples containing the maximum Pb concentrations, showing a high risk of CKD and SBP in high and extreme consumption groups. 相似文献
130.
Dagmara Panas Urszula Malinowska Tadeusz Piotrowski Jaros?aw ?ygierewicz Piotr Suffczyński 《PloS one》2013,8(4)
Spindles - a hallmark of stage II sleep - are a transient oscillatory phenomenon in the EEG believed to reflect thalamocortical activity contributing to unresponsiveness during sleep. Currently spindles are often classified into two classes: fast spindles, with a frequency of around 14 Hz, occurring in the centro-parietal region; and slow spindles, with a frequency of around 12 Hz, prevalent in the frontal region. Here we aim to establish whether the spindle generation process also exhibits spatial heterogeneity. Electroencephalographic recordings from 20 subjects were automatically scanned to detect spindles and the time occurrences of spindles were used for statistical analysis. Gamma distribution parameters were fit to each inter-spindle interval distribution, and a modified Wald-Wolfowitz lag-1 correlation test was applied. Results indicate that not all spindles are generated by the same statistical process, but this dissociation is not spindle-type specific. Although this dissociation is not topographically specific, a single generator for all spindle types appears unlikely. 相似文献