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931.
Hus I Bojarska-Junak A Dmoszyńska A Wasik-Szczepanek E Sieklucka M Trześniewska W Glazer M Roliński J 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2008,46(2):147-152
Recently identified biological risk factors in B-cell chronic lymphocytic leukemia (B-CLL) include ZAP-70 and CD38 expression. The present study was conducted to clarify whether a combined analysis could improve predictive impact of these two parameters. We examined the expression of ZAP-70 and CD38 by flow cytometry method in 217 newly diagnosed, consecutive, unselected and well characterized B-CLL patients in relation to laboratory parameters and clinical outcome. We confirmed that both ZAP-70 as well as CD38 were independent of prognostic factors. There was a significant correlation between the percentage of leukemic cells positive for ZAP-70 and the percentage of CD38+CD19+ cells (R=0.629; p=0.000001). Combined analysis of ZAP-70 and CD38 showed concordant results in 158/217 patients (72.8%), while in 59 patients the results were discordant (27.2%). A mean treatment free survival (TFS) was the longest in ZAP-70-CD38-patients (45.6 months, comparing to 13.6 months in ZAP-70+CD38+ group). Also a mean overall survival was the longest in ZAP-70-CD38- patients (224.7 months compared to 77.9 months in ZAP-70+CD38+ patients). 相似文献
932.
Danuta Chołuj Romualda Karwowska Agnieszka Ciszewska Marta Jasińska 《Acta Physiologiae Plantarum》2008,30(5):679-687
Accumulation of various osmolytes was examined in plants of sugar beet cv. Janus grown under two soil water treatments: control
(60% of the field water capacity; FWC) and drought (30–35% FWC). The water shortage started on the 61st day after emergence
(DAE), at the stage of the beginning of tap-roots development and was imposed for 35 days. Osmotic potential of sugar beet
plant organs, particularly tap-roots, was decreased significantly as a consequence of a long-term drought. Water shortage
reduced univalent (K+, Na+) cations concentrations in the petioles and divalent (Ca2+, Mg2+) ions level in the mature and old leaves. Cation concentrations in the tap-roots were not affected by water shortage. The
ratio of univalent to divalent cations was significantly increased in young leaves and petioles as a consequence of drought.
Long-term water deficit caused a significant reduction of inorganic phosphorus (Pi) concentration in young and old leaves. Under the water stress condition, the concentration of proline was increased in all
individual plant organs, except proline concentration in the youngest leaves. Drought treatment caused a significant increase
of glycine betaine content in shoot without any change in tap-roots. Glucose concentrations were significantly increased only
in tap-roots as the effect of drought. In response to water shortage the accumulation of sucrose was observed in all the examined
leaves and tap-roots. Overall, a long-term drought activated an effective mechanism for osmotic adjustment both in the shoot
and in the root tissues which may be critical to survival rather than to maintain plant growth but sugar beet organs accumulate
different solutes as a response to water cessation. 相似文献
933.
Bojko B Sułkowska A Maciazek M Równicka J Njau F Sułkowski WW 《International journal of biological macromolecules》2008,42(4):314-323
Saturated fatty acids such as myristic acid play an important role in the pathogenesis of cardiovascular disorders.
Using the quenching fluorescence method we examined the influence of myristate on the changes of transporting protein affinity towards aspirin—the most popular anticoagulant.
Our results showed that the presence of the myristic acid alters the stability of the anticoagulant–albumin complex. The ranges of [myristate]/[albumin] molar ratio at which the stability of drug–protein complex increases or decreases were determined. The differences in interaction between ligands and human or bovine serum albumins were identified. The competition in binding of ligands with these albumins was also described. 相似文献
934.
Crisponi G Nurchi VM Pivetta T Gałezowska J Gumienna-Kontecka E Bailly T Burgada R Kozłowski H 《Journal of inorganic biochemistry》2008,102(7):1486-1494
Coordination properties toward Fe(III) and Al(III) of a mixed bisphosphonate-hydroxypyridinonate ligand are presented. Potentiometric, spectrophotometric and NMR results allowed to conclude that Fe(III) and Al(III) coordination takes place on the pyridinone moiety. The high steric hindrance prevents the possibility of simultaneous coordination of both groups to the same metal ion. Quantum mechanical calculations confirm this finding allowing to determine the minimal length of the linker necessary for a stable conformation of complexes in which Fe(III) is coordinated both by pyridinone and bisphosphonate groups. 相似文献
935.
Recently published biochemical data suggest the significant role of selenium compounds as the adjuvants combined with L: -thyroxine therapy, which can reduce antithyroid peroxidase antibodies' (TPOAb) levels in patients with Hashimoto disease. The study was undertaken to document in a more detailed way the changes in parameters expressing the thyroid and ovarian function brought about by selenium supplementation (50-100 microg/day) in a woman undergoing autoimmune thyroiditis (AIT) therapy. This prospective observational case study lasted for 14 months plus additional 5 months as a follow-up period. Parameters reflecting selenium status, thyroid metabolism, and sex hormones secretion were determined at the onset and end of the study period, as well as in some of its middle points. During the supplementation trial, serum selenium (Se) increased by 45% and plasma glutathione peroxidase (GPX3) by 21%. TPOAb decreased by 76%. All other parameters also fluctuated during the supplementation period, but all results were always within normal physiological ranges. After withdrawal of the supplementation, the sharp fall of Se and GPX3 promptly occurred, and this phenomenon was accompanied with a marked increase in TPOAb. This report stresses the importance of selenium supplementation in AIT treatment. However, the efficiency and durability of the effect of Se supplementation on the TPOAb titer remain an open question. The clarification of mechanism(s) underlying Se interaction with autoimmune processes should throw new light on this issue. 相似文献
936.
Zinc is a multi-functional element that is found in almost 300 enzymes where it performs catalytic, co-catalytic, and/or structural
functions. In 1982, Gordon et al. (Am J Clin Ntr 35:849–857, 1982) found that a low zinc diet caused poor platelet aggregation
and increased bleeding tendency in adult males. This fact drew interest to the role of zinc in blood clotting. It has been
shown that hyperzincemia predisposes to increased coagulability, and hypozincemia to poor platelet aggregation and increased
bleeding time. The blood clotting disturbances can be regressed by appropriate zinc intake management. Considering the importance
of zinc as an essential element, its participation in regulation of the equilibrium between pro- and anti-thrombotic factors
originating in platelets and endothelium prompted further investigations. 相似文献
937.
Edyta Skrzypek Ilona Czyczyło-Mysza Izabela Marcińska Maria Wędzony 《Plant Cell, Tissue and Organ Culture》2008,94(2):131-137
Anthers cultures of six Polish cultivars of pasture lupin (Lupinus L.) were examined for their androgenic response. Anthers with microspores at the uninucleate stage were isolated from flower
buds and cultured in liquid media. Better viability of androgenetic structures was obtained when donor plants had grown under
field as opposed to greenhouse conditions. A density of five anthers per 0.5 ml medium was more conducive to androgenetic
induction than 25 anthers per 0.5 ml medium. Addition of 5% maltose to the induction medium and culture at 25°C without pre-treatment
of flowers, buds or anthers promoted microspore release and division. The greatest frequency of androgenic callus, ~70% was
developed from cvs. Katon, Wat (white lupin), in contrast to cvs. Legat, Juno (yellow lupin), Polonez and Sonet (narrow-leafed
lupin) with callus induction ~30–40%. Despite various combinations of media tested, plant regeneration was not obtained from
anther derived callus. 相似文献
938.
Guranowski A Wojdyła AM Pietrowska-Borek M Bieganowski P Khurs EN Cliff MJ Blackburn GM Błaziak D Stec WJ 《FEBS letters》2008,582(20):3152-3158
We show here that Fhit proteins, in addition to their function as dinucleoside triphosphate hydrolases, act similarly to adenylylsulfatases and nucleoside phosphoramidases, liberating nucleoside 5'-monophosphates from such natural metabolites as adenosine 5'-phosphosulfate and adenosine 5'-phosphoramidate. Moreover, Fhits recognize synthetic nucleotides, such as adenosine 5'-O-phosphorofluoridate and adenosine 5'-O-(gamma-fluorotriphosphate), and release AMP from them. With respect to the former, Fhits behave like a phosphodiesterase I concomitant with cleavage of the P-F bond. Some kinetic parameters and implications of the novel reactions catalyzed by the human and plant (Arabidopsis thaliana) Fhit proteins are presented. 相似文献
939.
Małkowski A Sobolewski K Jaworski S Bańkowski E 《Molecular and cellular biochemistry》2008,311(1-2):137-143
Our previous study reported that TGF-β may be isolated from human Wharton’s jelly (WJ) in a form of soluble, high molecular
complex(es). We decided to study the effect of extracellular matrix degradation and reduction of disulphide bridges reduction
on the release of TGF-β from WJ. The WJ prepared from the umbilical cords of newborns delivered at term by healthy mothers
was homogenised and treated with hyaluronidase, collagenase, heparinase, chondroitinase and β-mercaptoethanol, the resulting
extracts were then submitted to TGF-β immunoassay and SDS/PAGE followed by Western immunoblotting. The effect of metalloproteinase
activation on TGF-β was also studied. Pre-treatment of WJ homogenates with hyaluronidase or collagenase markedly increased
the extractability of TGF-β, but did not dissociate the complexes. In contrast, the action of β-mercaptoethanol resulted in
the release of free TGF-β; but activation of metalloproteinases resulted in the disappearance of this factor. We conclude
that TGF-β1 is bound through disulphide bonds to an extracellular matrix component of WJ. The large amount of collagen fibrils
and hyaluronate molecules which surround the cells scattered in WJ may prevent the access of extracting solution to TGF-β
causing a low extractability of this factor. Although hyaluronate and collagen do not bind TGF-β directly, they may present
a barrier that prevents the diffusion of TGF-β in WJ and results in its concentration around the cells thereby facilitating
its interaction with membrane receptors and subsequent stimulation of cell division and synthesis of extracellular matrix
components. 相似文献
940.
Masłyk M Kochanowicz E Zieliński R Kubiński K Hellman U Szyszka R 《Molecular and cellular biochemistry》2008,312(1-2):61-69
Since Svf1 is phosphoprotein, we investigated whether it was a substrate for protein kinase CK2. According to the amino acid
sequence Svf1 harbours 20 putative CK2 phosphorylation sites. Here, we have reported cloning, overexpression, purification
and characterization of yeast Svf1 as a substrate for three forms of yeast CK2. Svf1 serves as a substrate for both the recombinant
CK2α (K
m 0.35 μM) and CK2α′ (K
m 0.18 μM) as well as CK2 holoenzyme (K
m 1.1 μM). Different K
m values argue that CK2β(β′) subunit has an inhibitory effect on the activity of both CK2α and CK2α′ towards surviving factor
Svf1. Reconstitution of α′2ββ′ isoform of CK2 holoenzyme shows that β/β′ subunits have regulatory effect depending on the kind of CK2 catalytic subunit.
This effect was not observed in the case of α2ββ′ isoform, which may be due to interaction between Svf1 and regulatory CK2β subunit (shown by co-immunoprecipitation experiments).
Interactions between CK2 subunits and Svf1 protein may have influence on ATP as well as ATP-competitive inhibitors (TBBt and
TBBz) binding. CK2 phosphorylates up to six serine residues in highly acidic peptide K199EVIPESDEEESSADEDDNEDEDEESGDSEEESGSEEESDSEEVEITYED248 of the Svf1 protein in vitro. Presented data may help to elucidate the role of protein kinase CK2 and Svf1 in the regulation
of cell survival pathways. 相似文献