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Autologous blood derived products, such as platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are widely applied in regenerative therapies, in contrast to the drawbacks in their application, mainly deriving from the preparation methods used. Eliminating the disadvantages of both PRP and PRF, hyperacute serum (HAS) opens a new path in autologous serum therapy showing similar or even improved regenerative potential at the same time. Despite the frequent experimental and clinical use of PRP and HAS, their protein composition has not been examined thoroughly yet. Thus, we investigated and compared the composition of HAS, serum, PRP and plasma products using citrate and EDTA by simple laboratory tests, and we compared the composition of HAS, serum, EDTA PRP and plasma by Proteome Profiler and ELISA assays. According to our results the natural ionic balance was upset in both EDTA and citrate PRP as well as in plasma. EDTA PRP contained significantly higher level of growth factors and cytokines, especially platelet derived angiogenic and inflammatory proteins, that can be explained by the significantly higher number of platelets in EDTA PRP. The composition analysis of blood derivatives revealed that although the preparation method of PRP and HAS were similar, the ionic and protein composition of HAS could be advantageous for cell function.

Main conclusion The accumulation of NiCo following the termination of the accumulation of iron in chloroplast suggests that NiCo is not solely involved in iron uptake processes of chloroplasts.Abstract Chloroplast iron (Fe) uptake is thought to be operated by a complex containing permease in chloroplast 1 (PIC1) and nickel-cobalt transporter (NiCo) proteins, whereas the role of other Fe homeostasis-related transporters such as multiple antibiotic resistance protein 1 (MAR1) is less characterized. Although pieces of information exist on the regulation of chloroplast Fe uptake, including the effect of plant Fe homeostasis, the whole system has not been revealed in detail yet. Thus, we aimed to follow leaf development-scale changes in the chloroplast Fe uptake components PIC1, NiCo and MAR1 under deficient, optimal and supraoptimal Fe nutrition using Brassica napus as model. Fe deficiency decreased both the photosynthetic activity and the Fe content of plastids. Supraoptimal Fe nutrition caused neither Fe accumulation in chloroplasts nor any toxic effects, thus only fully saturated the need for Fe in the leaves. In parallel with the increasing Fe supply of plants and ageing of the leaves, the expression of BnPIC1 was tendentiously repressed. Though transcript and protein amount of BnNiCo tendentiously increased during leaf development, it was even markedly upregulated in ageing leaves. The relative transcript amount of BnMAR1 increased mainly in ageing leaves facing Fe deficiency. Taken together chloroplast physiology, Fe content and transcript amount data, the exclusive participation of NiCo in the chloroplast Fe uptake is not supported. Saturation of the Fe requirement of chloroplasts seems to be linked to the delay of decomposing the photosynthetic apparatus and keeping chloroplast Fe homeostasis in a rather constant status together with a supressed Fe uptake machinery.

Some of the key epigenetic regulatory mechanisms appeared early during evolution, and the acquisition of novel epigenetic regulators apparently facilitated certain evolutionary transitions. In this short review we focus mainly on the major epigenetic mechanisms that control chromatin structure and accessibility in mammalian cells. The enzymes methylating CpG dinucleotides and those involved in the active demethylation of 5-metylcytosine (5mC) are outlined together with the members of the methyl binding protein (MBP) family that bind to and "interpret" the 5mC mark. The enzymes involved in reversible, covalent modifications of core histone proteins that affect chromatin structure are also described briefly. Proteins that build up Polycomb group (PcG) and Trithorax group (TrxG) protein complexes may also modify histones. By establishing heritable chromatin states, PcG and TrxG complexes contribute - similarly to cytosine methylation - to the transmission of cell type-specific gene expression patterns from cell generation to cell generation. Novel players involved in epigenetic regulation, including variant histones, pioneer transcription factors, long noncoding RNA molecules and the regulators of long-distance chromatin interactions are introduced as well, followed by the characterization of various chromatin types.

We analyzed the levels of acetylated histones and histone H3 dimethylated on lysine 4 (H3K4me2) at the LMP2A promoter (LMP2Ap) of Epstein-Barr virus in well-characterized type I and type III lymphoid cell line pairs and additionally in the nasopharyngeal carcinoma cell line C666-1 by using chromatin immunoprecipitation. We found that enhanced levels of acetylated histones marked the upregulated LMP2Ap in lymphoid cells. In contrast, in C666-1 cells, the highly DNA-methylated, inactive LMP2Ap was also enriched in acetylated histones and H3K4me2. Our results suggest that the combinatorial effects of DNA methylation, histone acetylation, and H3K4me2 modulate the activity of LMP2Ap.Epstein-Barr virus (EBV) is closely associated with a variety of neoplasms. In latently infected cells, depending on the gene expression pattern, three main classes of latency have been described (17). Latent membrane protein 2A (LMP2A) is transcribed from the LMP2A promoter (LMP2Ap) in large quantities in type III latency, at variable levels in type II latency, and at low levels or not at all in type I latency (15,20,32).Previous in vitro binding and reporter gene experiments charted two CBF1 sites and other elements in the regulatory region of LMP2Ap (10,15,18,[30][31][32]. Our previous in vivo analysis of LMP2Ap showed that, in lymphoid cell lines, the characteristic footprints on two CBF1 and further binding sites, together with the overall hypomethylation of CpG dinucleotides, correlate well with promoter activity. In contrast, the absence of several genomic footprints, as well as the presence of patches of highly methylated CpG dinucleotides, is characteristic of silent LMP2Ap's in lymphoid cells (20). However, in addition to DNA methylation and protein-DNA interactions, the acetylation of histone H3 and H4 and methylation on the lysine 4 residue of histone H3 may play an important role in the regulation of LMP2Ap, as they lead to chromatin relaxation and subsequent modulation of gene expression (4,7,16,24,26). It was also shown previously that the binding of EBNA2 to CBF1 directs the p300, CBP, and P/CAF histone acetyltransferase coactivators to the LMP1 promoter (28). On the other hand, CBF1 in the absence of EBNA2 or activated NotchIC represses transcription, in part by tethering a histone deacetylase corepressor complex (11)(12)(13)29). Furthermore, previous studies have shown good correlation between the levels of acetylated histones and histone H3 dimethylated at the lysine 4 residue (H3K4me2) and the activity of the CBF1-regulated C-promoter of EBV (1, 5; G. Fejer et al., submitted for publication). Therefore, we wished to analyze the levels of acetylated histone H3 (AcH3), acetylated histone H4 (AcH4), and H3K4me2 at LMP2Ap in well-characterized type I (Mutu-BL-I-Cl-216 and Rael) and type III (Mutu-BL-III-Cl-99 and CB-M1-Ral-STO) lymphoid cell line pairs carrying the same viral strains (20, 21) and additionally in the only available EBV-positive nasopharyngeal carcinoma (NPC) cell line, C666-1, representative of latency type...