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The solid-phase protein assays using blotting membranes as hard support do not allow achieving the low background and sensitivity of protein staining in clear gels. The membrane opacity complicates imaging of results on standard lab documentation systems. We describe a low-cost transparent matrix that can be used as an alternative to polymeric membranes for solid-phase assays. Protein samples are spotted onto a dry film of composite agarose–polyacrylamide matrix covering standard glass microscopic slides. After rehydration in protein-fixing solution, matrix with protein samples can be detached from glass support and stained as conventional protein polyacrylamide gels.  相似文献   
23.
Evidence is emerging that many diseases result from defects in gene functions, which, in turn, depend on the local chromatin environment of a gene. However, it still remains not fully clear how chromatin activity code is ‘translated’ to the particular ‘activating’ or ‘repressing’ chromatin structural transition. Commonly, chromatin remodeling in vitro was studied using mononucleosomes as a model. However, recent data suggest that structural reorganization of a single mononucleosome is not equal to remodeling of a nucleosome particle under multinucleosomal content – such as, interaction of nucleosomes via flexible histone termini could significantly alter the mode (and the resulting products) of nucleosome structural transitions. It is becoming evident that a nucleosome array does not constitute just a ‘polymer’ of individual ‘canonical’ nucleosomes due to multiple inter-nucleosomal interactions which affect nucleosome dynamics and structure. It could be hypothesized, that inter-nucleosomal interactions could act in cooperation with nucleosome inherent dynamics to orchestrate DNA-based processes and promote formation and stabilization of highly-dynamic, accessible structure of a nucleosome array. In the proposed paper we would like to discuss the nucleosome dynamics within the chromatin fiber mainly as it pertains to the roles of the structural changes mediated by inter-nucleosomal interactions.  相似文献   
24.
The inheritable methylation pattern of gene activity, created upon cell differentiation, is further maintained by the “SET” (methyltransferase)-domain proteins. However, it is still not clear how SET-proteins can decide on the required gene activity state and the way their chromatin association is maintained. Here we have found that high levels of histone acetylation - the hallmarks of active chromosome regions in vivo - can increase the affinity of reconstituted nucleosomes to the SET domain of ALL-1 histone methyltransferase in a defined system in vitro.  相似文献   
25.
Abstract: Development as well as current status of the knowledge of nonhuman primate blood groups are discussed together with some practical implications of the red cell antigen polymorphisms in anthropoid apes, Old and New World monkeys and prosimians. Recent data on molecular biology and genetics throw light on the relationships among simian and human red cell antigens and their evolutionary pathways.  相似文献   
26.
The analysis included 53 patients (32 men and 21 women) aged 43 to 66 years, who were subjected to radical treatment (surgical or combined) because of stomach (22 patients) or large bowel (31 patients) cancer. All the patients were included in the same model of control examinations, which considered evaluation of the erythrocytes TAS and of the Ca19-9, CEA and AFP concentrations in serum. It was confirmed that in all the patients in whom the recurrence and/or the dissemination occurred of the cancer, the average erythrocytes TAS value increased 5.5 times by comparison with the period before progression and 7 times in comparison with the patients without recurrence and/or dissemination of the cancer. Moreover it was shown that statistically significantly higher TAS values were associated with the progression of the large bowel cancer in comparison with the stomach cancer and that the blood cells TAS positively correlated with the changes of the Ca19-9, CEA and AFP concentrations in patients with progression of the cancer after radical treatment.  相似文献   
27.
Leptin is a hormone synthesized and secreted primarily in adipose cells that help to regulate energy balance. This study examined the associations of single nucleotide polymorphisms in the rabbit leptin gene with growth traits, slaughter traits and physicochemical parameters of New Zealand White (NZW) and Belgian Giant Grey (BGG) crossbreed rabbits. In total, 320 crossbreed animals were genotyped for polymorphisms within exon 2—g.16081633T>C, intron 1_2—g.16081420C>T, and within UTR—g.16079636C>G for association analysis. Identified polymorphisms within rabbits leptin gene showed significant differences for dissectible fat percentage in carcass and dissectible fat weight in intermediate part (g.16081633T>C). Moreover, meat traits like protein content (g.16081633T>C; g.16079636C>G), intramuscular fat content (g.16081633T>C; g.16079636C>G, g.16081420C>T), dry matter (g.16081420C>T), ash (g.16081420C>T), water (g.16081420C>T), and cohesiveness (g.16081420C>T, g.16079636C>G) were affected by polymorphisms in leptin gene. We conclude that polymorphism in the rabbit leptin gene influences important carcass and meat traits of NZW?×?BGG crossbreeds. Therefore, polymorphisms identified in this study may be used in selection as a meat trait markers.  相似文献   
28.
For practical purposes two classes of blood groups of Old World monkeys can be distinguished: human-type and simian-type, depending on the kind of reagents used for testing. Of the human-type blood groups, only the A-B-O groups, defined by saliva inhibition and serum tests, are polymorphic in some, but not all, monkey species. The distributions of those groups show wide differences not only among monkey species but also among troops of one and the same species. The tests for other human-type antigens give with the monkey red cells either uniformly positive or uniformly negative results. Thus, the human-type blood groups seem to be of limited use as taxonomic tools in the systematics of the Old World monkeys.On the other hand, the simian-type blood groups, defined by isoor crossimmune monkey sera, display highly polymorphic patterns in most species of Old World monkeys, and the capability of the antisera to react with combining groups on the red cells of monkeys of closely related species seems to reflect the taxonomic closeness of two or more species. The fact that some of the simian-type specificities, notably those belonging to the rhesus Drh graded blood group system, are shared by many species of Old World monkeys, indicates that they were introduced into genotypes during early stages of evolution of the Cercopithecidae.  相似文献   
29.
A cell-free system derived from Drosophila embryos was used to investigate positioning of nucleosomes on specific DNA sequences. This system can be used to reconstitute differently acetylated nucleosome arrays possessing ATP-dependent dynamic properties that are not observed with chromatin assembled from pure components. Nucleosome positioning on different DNA sequences was studied by restriction endonuclease assay. The sequence of DNA and the acetylation status of histones had profound effects on the distribution of nucleosomes, suggesting their cooperative effect on nucleosome repositioning.  相似文献   
30.
The mechanisms of protective effect of N-methyl-D-aspartate (NMDA) receptor stimulation on apoptosis of neurons at their early stage of development are poorly understood. In the present study, we investigated the effects of NMDA on staurosporine (St)- and low-potassium (LP)-evoked apoptotic cell death in primary cerebellar granule cell (CGC) cultures at 7 days in vitro (DIV). We found that NMDA (200 μM) attenuated the St (0.5 μM)- and LP (5 mM KCl)-induced neuronal cell death in 7 but not 12 DIV CGC as confirmed by LDH release and MTT reduction assays. Moreover, NMDA attenuated St-and LP-evoked DNA fragmentation and cytosolic apoptosis inducing factor (AIF) protein level but not caspase-3 activation induced by both pro-apoptotic factors. Neuroprotective effects of NMDA on St-induced apoptosis in CGC were attenuated by inhibitors of ERK/MAPK-signaling, PD 98059 and U0126 but not by NMDA receptor antagonists, AP-5 (100 μM) and MK-801 (1 μM) or by inhibitors of PI3-K/Akt pathway (LY 294002 and wortmannin). In contrast to staurosporine model of apoptosis, AP-5 and MK-801 but not inhibitors of PI3-K/Akt and MAPK/ERK1/2 prevented the NMDA-mediated neuroprotection in LP-induced apoptosis of CGC. In separate experiments, we observed also the anti-apoptotic action of NMDA on St (0.5 μM)- and salsolinol (250 μM)-evoked cell death in human neuroblastoma SH-SY5Y cells without its influence on caspase-3 activity, induced by these pro-apoptotic factors. These data indicate that neuroprotection evoked by NMDA in CGC strongly depends on used pro-apoptotic agent and could engage NMDA channel function or be connected with the activation of pro-survival MAPK/ERK1/2 pathway. It is also suggested that anti-apoptotic effects of NMDA is connected with inhibition of fragmentation of DNA via caspase-3-independent mechanism.  相似文献   
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