Single-layer DNA origami is an efficient method for programmable self-assembly of nanostructures approximating almost any desired two-dimensional shape from ~5 MDa of DNA building material. In this method, a 7 kilobase single “scaffold” strand is assembled with hundreds of oligodeoxyribonucleotide “staple” strands to form a parallel array of double helices. Multiple layers of such DNA sheets also can be designed to assemble into a stack, enabling construction of solid three-dimensional shapes with considerably greater mechanical rigidity than two-dimensional shapes; however, the folding yield often is much lower and the required folding times are much longer. Here we introduce two strategies for designing multi-layer DNA origami that demonstrate potential for boosting assembly yield: (1) individual base pairs can be inserted between crossovers, allowing for greater bowing of helices at positions away from crossovers and therefore reduced electrostatic repulsion. At the same time, this underwinding of double helices increases a destabilizing torsional strain energy but then also increases affinity for intercalators, and binding of such intercalators can relieve this stress. We also have exploited this enhanced affinity for intercalators to PEGylate the surface of the nanostructures in a noncovalent fashion using PEG-tris-acridine. (2) Positioning of staple-strand breaks in the DNA origami such that each staple strand includes a 14 nucleotide (nt) continuous segment that binds to a complementary 14 nt continuous segment of the scaffold can greatly improve folding yields.

Continuous-flow left ventricular assist devices (CF-LVADs) have significantly improved outcomes for patients with end-stage heart failure when used as a bridge to cardiac transplantation or, more recently, as destination therapy. However, its implantations carries a risk of complications including infection, device malfunction, arrhythmias, right ventricular failure, thromboembolic disease, postoperative and nonsurgical bleeding. A significant number of left ventricular assist devices (LVAD) recipients may experience recurrent gastrointestinal hemorrhage, mainly due to combination of antiplatelet and vitamin K antagonist therapy, activation of fibrinolytic pathway, acquired von Willebrand factor deficiency, and tendency to develop small intestinal angiodysplasias due to increased rotary speed of the pump. Gastrointestinal bleeding in LVAD patients remains a source of increased morbidity including the need for blood transfusions, extended hospital stays, multiple readmissions, and overall mortality. Management of gastrointestinal bleeding in LVAD patients involves multidisciplinary approach in stabilizing the patients, addressing risk factors and performing structured endoluminal evaluation with focus on upper gastrointestinal tract including jejunum to find and eradicate culprit lesion. Medical and procedural intervention is largely successful and universal bleeding cessation occurs in transplanted patients.

Background and purpose:The increased levels of extracellular adenosine in inflamed tissues down-regulate activated immune cells via the A2A adenosine receptor. This A2A adenosine receptor-mediated immunosuppression is a disqualifying obstacle in cancer immunotherapy as it protects cancerous tissues from adoptively transferred anti-tumour T cells. The aim of this study was to test whether the negative selection of T cells will produce T cells that are resistant to inhibition by extracellular adenosine. Experimental approach: Cytotoxic T lymphocytes (CTL) were developed by mixed lymphocyte culture in the presence or absence of the adenosine receptor agonist 5′-N-ethylcarboxamidoadenosine (NECA). The sensitivity of CTL to adenosine analogues was characterized by cAMP induction, interferon-g production and cytotoxicity. Key results: CTL that could proliferate even in the presence of NECA were less susceptible to inhibition by A2A adenosine receptor agonists, as shown by a much smaller accumulation of cAMP and less inhibition of interferon-g production compared with control CTL. The successful protocol to produce CTL that are both resistant to adenosine-mediated immunosuppression and maintain strong cytotoxicity and interferon-g secretion required NECA to be added only during the expansion stage after the establishment of CTL. In contrast, the priming of resting T cells in the presence of NECA resulted in T cells with impaired effector functions. Conclusions and implications: Adenosine-resistant effector T cells were successfully obtained by exposure of activated T cells to NECA. These in vitro studies form the basis for future attempts to produce anti-tumour T cells that are more effective in adoptive immunotherapy.

The major focus of this paper is to describe and evaluate current information on the role of natural killer cells (NK cells) in the pathogenesis of blistering diseases. Until now, only pemphigus vulgaris (PV) has been studied. One co-culture study demonstrated that CD4+ T cells from the peripheral blood or perilesional skin of patients with active disease proliferate and secrete cytokines in the presence of major histocompatibility class II-expressing NK cells loaded with antigenic desmoglein self-peptides. Another study showed that NK cells can contribute to a T helper type 2-biased immune response through impaired interleukins (IL)-12 signaling and upregulation of IL, IL-10 and IL-5. Although significant data on other blistering diseases are unavailable at present, some studies implicate NK cells in disease progression. For instance, information on the role of NK cells in psoriasis and their production of tumor necrosis factor-α (TNF-α) will be provided since several TNF-α-inhibitors are used in its treatment. Studies on alopecia areata are also included in this paper because NK cells seem to play a key role in its pathogenesis. This review highlights the potential importance of NK cells and NKT cells as members of the large repertoire of cells and soluble mediators that play a critical role in pathogenesis of blistering diseases and other autoimmune diseases involving the skin. Therefore, the authors advocate a greater focus and interest on the study of the interaction of NK cells and the skin.