instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: Chromatin epigenetics participate in control of gene expression during metazoan development. DNA methylation and post-translational modifications (PTMs) of histones have been extensively characterised in cell types present in, or derived from, mouse embryos. In embryonic stem cells (ESCs) derived from blastocysts, factors involved in deposition of epigenetic marks regulate properties related to self-renewal and pluripotency. In the germ lineage, changes in histone PTMs and DNA demethylation occur during formation of the primordial germ cells (PGCs) to reset the epigenome of the future gametes. Trimethylation of histone H3 on lysine 27 (H3K27me3) by Polycomb group proteins is involved in several epigenome-remodelling steps, but it remains unclear whether these epigenetic features are conserved in non-mammalian vertebrates. To investigate this question, we compared the abundance and nuclear distribution of the main histone PTMs, 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) in chicken ESCs, PGCs and blastodermal cells (BCs) with differentiated chicken ESCs and embryonic fibroblasts. In addition, we analysed the expression of chromatin modifier genes to better understand the establishment and dynamics of chromatin epigenetic profiles.', 'The nuclear distributions of most PTMs and 5hmC in chicken stem cells were similar to what has been described for mammalian cells. However, unlike mouse pericentric heterochromatin (PCH), chicken ESC PCH contained high levels of trimethylated histone H3 on lysine 27 (H3K27me3). In differentiated chicken cells, PCH was less enriched in H3K27me3 relative to chromatin overall. In PGCs, the H3K27me3 global level was greatly reduced, whereas the H3K9me3 level was elevated. Most chromatin modifier genes known in mammals were expressed in chicken ESCs, PGCs and BCs. Genes presumably involved in de novo DNA methylation were very highly expressed. DNMT3B and HELLS/SMARCA6 were highly expressed in chicken ESCs, PGCs and BCs compared to differentiated chicken ESCs and embryonic fibroblasts, and DNMT3A was strongly expressed in ESCs, differentiated ESCs and BCs.\Question: Do chicken embryonic stem cells and primordial germ cells display different heterochromatic histone marks than their mammalian counterparts?
answer:
Chicken ESCs and PGCs differ from their mammalian counterparts with respect to H3K27 methylation. High enrichment of H3K27me3 at PCH is specific to pluripotent cells in chicken. Our results demonstrate that the dynamics in chromatin constitution described during mouse development is not universal to all vertebrate species.

question:
Context: Allogeneic mesenchymal stem cells (MSCs) exhibit therapeutic effects in human autoimmune diseases such as systemic lupus erythematosus (SLE), but the underlying mechanisms remain largely unknown. The aim of this study was to investigate how allogeneic MSCs mediate immunosuppression in lupus patients.', 'The effects of allogeneic umbilical cord-derived MSCs (UC-MSCs) on inhibition of T cell proliferation were determined. MSC functional molecules were stimulated with peripheral blood mononuclear cells from healthy controls and SLE patients and examined by real-time polymerase chain reaction. CD4+ and CD8+ T cells were purified using microbeads to stimulate MSCs in order to determine cytokine expression by MSCs and to further determine which cell subset(s) or which molecule(s) is involved in inhibition of MSC-mediated T cell proliferation. The related signaling pathways were assessed. We determined levels of serum cytokines in lupus patients before and after UC-MSC transplantation.', 'Allogeneic UC-MSCs suppressed T cell proliferation in lupus patients by secreting large amounts of indoleamine 2,3-dioxygenase (IDO). We further found that interferon- (IFN), which is produced predominantly by lupus CD8+ T cells, is the key factor that enhances IDO activity in allogeneic MSCs and that it is associated with IFNGR1/JAK-2/STAT signaling pathways. Intriguingly, bone marrow-derived MSCs from patients with active lupus demonstrated defective IDO production in response to IFN and allogeneic CD8+ T cell stimulation. After allogeneic UC-MSC transplantation, serum IDO activity increased in lupus patients.\Question: Is a CD8 T cell/indoleamine 2,3-dioxygenase axis required for mesenchymal stem cell suppression of human systemic lupus erythematosus?
answer:
We found a previously unrecognized CD8+ T cell/IFN/IDO axis that mediates the therapeutic effects of allogeneic MSCs in lupus patients.

question:
Context: In recent years, the concept of prosthodontic-driven implantology has received more attention. The precise placement of implants in accordance with greater safety and confidence allow the practitioner to offer a safer, more secure and predictable treatment than could previously be provided. In this report, this novel approach is illustrated through description of 1 difficult case.', 'Using principles of computer-assisted design and rapid manufacturing, the data acquisitioned from computerized tomography was used to plan implant rehabilitation and to transfer this information to the surgery as well.', 'The procedure of implant planning in this sophisticated technique has potential to yield substantial public health benefits.\Question: Do a novel stereolithographic surgical guide template for planning treatment involving a mandibular dental implant?
answer:
It was demonstrated that the versatility of the technique allows not only precise translation of the treatment plan to the patient's mouth, but also offers many additional significant benefits including use of special guides during surgery which would be difficult to achieve with traditional procedures.