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61.
The purpose of the presented paper was to study the effect of high concentrations of tributyltin (TBT) on the potassium retention
and fatty acid (FA) composition of the fungus Cunninghamella elegans recognized as a very efficient TBT degrader. An increase in TBT had a strong influence on the potassium concentration in
the fungus. In growth medium without TBT, the potassium content of the fungal cells was 5.8 mg K+ g dry weight−1. The maximum concentration of K+ was 15.06 mg g−1 dry weight at 30 mg l−1 of TBT. The major FAs that characterized the tested strain were C16:0, C18:1, C18:2, C18:3 and C18:0. TBT in the concentration
range 5–30 mg l−1 strongly influenced the FA composition. In the presence of the organotin, the degree of saturation increased. It suggests
that the observed changes promote an increase in the lipid ordering of the membrane by reducing its permeability and inhibiting
potassium ion efflux. 相似文献
62.
Chris Dockendorff Shujuan Jin Madeline Olsen Mark Lautens Martin Coupal Lejla Hodzic Nathan Spear Kemal Payza Christopher Walpole Mirosław J. Tomaszewski 《Bioorganic & medicinal chemistry letters》2009,19(4):1228-1232
A series of 1-aminotetralin scaffolds was synthesized via metal-catalyzed ring-opening reactions of heterobicyclic alkenes. Small libraries of amides and amines were made using the amino group of each scaffold as a handle. Screening of these libraries against human opioid receptors led to the identification of (S)–(S)-5.2a as a high-affinity selective μ ligand (IC50 μ = 5 nM, κ = 707 nM, δ = 3,795 nM) displaying μ-agonist/antagonist properties due to its partial agonism (EC50 = 2.6 μM; Emax = 18%). 相似文献
63.
A colostral proline-rich polypeptide complex (PRP) consisting of over 30 peptides shows beneficial effects in Alzheimer’s disease (AD) patients when administered in the form of sublinqual tablets called Colostrinin. The aim of the present studies was to investigate whether nanopeptide fragment of PRP (NP) - one of the PRP complex components can affect aggregation of amyloid β (Aβ1-42). The effect of NP on Aβ aggregation was studied using Thioflavin T (ThT) binding, atomic force microscopy, and analyzing circular dichroism spectra. Results presented suggest that NP can directly interact with amyloid beta, inhibit its aggregation and disrupt existing aggregates acting as a β sheet breaker and reduce toxicity induced by aggregated forms of Aβ. 相似文献
64.
Beata P. Plitta Marcin Michalak Mirosława Z. Naskręt-Barciszewska Jan Barciszewski Paweł Chmielarz 《Plant Cell, Tissue and Organ Culture》2014,117(1):31-37
Pedunculate oak (Quercus robur) is an ecologically and economically important forest tree species which produces seeds that are classified as recalcitrant. Thus, cryopreservation of seed meristems is a method for long-term preservation of this germplasm in gene banks. During cryopreservation, many factors, such as desiccation, cryoprotection and cooling/rewarming, can induce stress in the frozen meristems. In this study, in vitro survival and the global DNA methylation level of plumules after cryoprotection, desiccation and cryostorage was evaluated. Results indicated that both desiccation and storage in liquid nitrogen have negligible influence on DNA methylation status of Q. robur plumules. These findings support the cryopreservation of plumules as an appropriate method for conservation of Q. robur germplasm. 相似文献
65.
Chmielewska M Dubińska-Magiera M Sopel M Rzepecka D Hutchison CJ Goldberg MW Rzepecki R 《Cell and tissue research》2011,344(1):97-110
Laminin-associated polypeptide 2 (LAP2) proteins are alternatively spliced products of a single gene; they belong to the LEM domain family and, in mammals, locate to the nuclear envelope (NE) and nuclear lamina. Isoforms lacking the transmembrane domain also locate to the nucleoplasm. We used new specific antibodies against the N-terminal domain of Xenopus LAP2 to perform immunoprecipitation, identification and localization studies during Xenopus development. By immunoprecipitation and mass spectrometry (LC/MS/MS), we identified the embryonic isoform XLAP2??, which was downregulated during development similarly to XLAP2??. Embryonic isoforms XLAP2?? and XLAP2?? were located in close association with chromatin up to the blastula stage. Later in development, both embryonic isoforms and the adult isoform XLAP2?? were localized in a similar way at the NE. All isoforms colocalized with lamin B2/B3 during development, whereas XLAP2?? was colocalized with lamin B2 and apparently with the F/G repeat nucleoporins throughout the cell cycle in adult tissues and culture cells. XLAP2?? was localized in clusters on chromatin, both at the NE and inside the nucleus. Embryonic isoforms were also localized in clusters at the NE of oocytes. Our results suggest that XLAP2 isoforms participate in the maintenance and anchoring of chromatin domains to the NE and in the formation of lamin B microdomains. 相似文献
66.
Maria Długaszek Mirosława Kaszczuk Monika Mularczyk-Oliwa 《Biological trace element research》2011,142(1):1-10
Urine is a clinical specimen often used in medical diagnostics for monitoring of elements concentrations and kidneys function.
We determined the contents of magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe), lead (Pb), and cadmium (Cd)
in 74 samples of 24-h urine (from 46 women and 28 men). The measurements were realized by the atomic absorption spectrometry
(AAS) with atomization in the flame (FAAS) and in the graphite furnace (GFAAS). The received results were the subject of statistical
analysis including the sex and age of volunteers. Moreover, correlations between the elements and the relationships between
age and amounts of excreted elements with urine were tested. We found the statistically significant higher content of Zn in
men’s urine than in women’s one. Moreover, both adult women and men (>18 years) excreted much more Ca in urine in comparison to young subjects. Only
in case of Pb the significant positive correlation between its amount in 24-h urine of all donors and age was stated. The
correlation analysis has shown the significant positive relationships between Ca–Mg, Ca–Fe, Mg–Fe, Cu–Fe, Cu–Cd, Fe–Cd, and
Pb–Cd in total samples of urine. Basing on our results, we concluded that the gender and age of donors may impact on the elemental
status of 24-h urine. 相似文献
67.
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
68.
Prochorec-Sobieszek M Rymkiewicz G Makuch-Łasica H Majewski M Michalak K Rupiński R Warzocha K Maryniak R 《Arthritis research & therapy》2008,10(3):R55-12
Introduction
The purpose of this study was to analyze the data of patients with T-cell large granular lymphocyte (T-LGL) lymphocytosis associated with inflammatory arthropathy or with no arthritis symptoms.Methods
Clinical, serological as well as histopathological, immuhistochemical, and flow cytometric evaluations of blood/bone marrow of 21 patients with T-LGL lymphocytosis were performed. The bone marrow samples were also investigated for T-cell receptor (TCR) and immunoglobulin (IG) gene rearrangements by polymerase chain reaction with heteroduplex analysis.Results
Neutropenia was observed in 21 patients, splenomegaly in 10, autoimmune diseases such as rheumatoid arthritis (RA) in 9, unclassified arthritis resembling RA in 2, and autoimmune thyroiditis in 5 patients. T-LGL leukemia was recognized in 19 cases. Features of Felty syndrome were observed in all RA patients, representing a spectrum of T-LGL proliferations from reactive polyclonal through transitional between reactive and monoclonal to T-LGL leukemia. Bone marrow trephines from T-LGL leukemia patients showed interstitial clusters and intrasinusoidal linear infiltrations of CD3+/CD8+/CD57+/granzyme B+ lymphocytes, reactive lymphoid nodules, and decreased or normal granulocyte precursor count with left-shifted maturation. In three-color flow cytometry (FCM), T-LGL leukemia cells demonstrated CD2, CD3, and CD8 expression as well as a combination of CD16, CD56, or CD57. Abnormalities of other T-cell antigen expressions (especially CD5, CD7, and CD43) were also detected. In patients with polyclonal T-LGL lymphocytosis, T cells were dispersed in the bone marrow and the expression of pan-T-cell antigens in FCM was normal. Molecular studies revealed TCRB and TCRG gene rearrangements in 13 patients and TCRB, TCRG, and TCRD in 4 patients. The most frequently rearranged regions of variable genes were Vβ-Jβ1, Jβ2 and Vγ If Vγ10-Jγ. Moreover, in 4 patients, additional rearrangements of IG kappa and lambda variable genes of B cells were also observed.Conclusion
RA and neutropenia patients represented a continuous spectrum of T-LGL proliferations, although monoclonal expansions were most frequently observed. The histopathological pattern and immunophenotype of bone marrow infiltration as well as molecular characteristics were similar in T-LGL leukemia patients with and without arthritis. 相似文献69.
The specificity of 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM) for nitric oxide was evaluated in in vitro systems. The probe was found fairly specific for nitric oxide. Potential sources of artifacts include the autoxidation of DAF-FM, potentiated by light, and its oxidation by sources of superoxide and peroxyl radicals, leading to fluorescence spectra indistinguishable from those of the nitric oxide adduct. Although DAF-FM reacts with peroxynitrite, this reaction seems to be of secondary importance under quasi-physiological conditions. On the other hand, a simultaneous presence of a nitric oxide source and a superoxide or hydrogen peroxide decreases or increases the fluorescence of DAF-FM, respectively, resulting in biased estimates of nitric oxide production. 相似文献
70.
Ewa Gajewska Ewa Niewiadomska Krzysztof Tokarz Mirosława Słaba Maria Skłodowska 《Journal of plant physiology》2013
In this study, we analyzed the toxic effect of Ni during the development of wheat shoots. Typical developmental alterations in carbon metabolism-related parameters reflecting changes associated with the transition of the seedlings from heterotrophic to autotrophic metabolism were observed in the control shoots between the 1st and the 4th days. Adverse effects of 50 and 100 μM Ni became evident starting from the 4th day of growth on the metal-containing media. We found that Ni-induced stimulation of phosphoenolpyruvate carboxylase (PEPC) activity coincided with decrease in the ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) level and with declines in net photosynthetic rate (PN) and stomatal conductance (gs). Application of Ni resulted in increased activities of several dehydrogenases: glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), isocitrate dehydrogenase (NADP-ICDH) and malate dehydrogenase (NADH-MDH). In contrast, the activities of malic enzymes (NADP-ME and NAD-ME) decreased due to Ni stress. Treatment with Ni led to accumulation of glucose and declined concentration of sucrose as well as considerable increases in concentrations of malic and citric acids. Our results indicate that Ni stress redirects the carbon metabolism of developing wheat shoots to provide carbon skeletons for synthesis of amino acids and organic acids as well as to supply reducing power to sustain normal metabolic processes and to support defense mechanisms against oxidative stress. 相似文献