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Cardiac ventricular pressure overload affects patients with congenital heart defects and can cause cardiac insufficiency. Grafts of stem cell–derived cardiomyocytes are proposed as a complementary treatment to surgical repair of the cardiac defect, aiming to support ventricular function. Here, we report successful engraftment of human induced pluripotent stem cell–derived cardiac lineage cells into the heart of immunosuppressed rhesus macaques with a novel surgical model of right ventricular pressure overload. The human troponin+ grafts were detected in low-dose (2 × 10 6 cells/kg) and high-dose (10 × 10 6 cells/kg) treatment groups up to 12 weeks post-injection. Transplanted cells integrated and progressively matched the organization of the surrounding host myocardium. Ventricular tachycardia occurred in five out of 16 animals receiving cells, with episodes of incessant tachycardia observed in two animals; ventricular tachycardia events resolved within 19 days. Our results demonstrate that grafted cardiomyocytes mature and integrate into the myocardium of nonhuman primates modeling right ventricular pressure overload.

Minimal myelination is proposed to be a contributing factor to the preferential nigral neuronal loss in Parkinson’s disease (PD). Similar to nigral dopaminergic neurons, sympathetic neurons innervating the heart have long, thin axons which are unmyelinated or minimally myelinated. Interestingly, cardiac sympathetic loss in PD is heterogeneous across the heart, yet the spatial relationship between myelination and neurodegeneration is unknown. Here, we report the mapping of myelin basic protein (MBP) expression across the left ventricle of normal rhesus macaques (n = 5) and animals intoxicated with systemic 6-OHDA (50 mg/kg iv) to model parkinsonian cardiac neurodegeneration (n = 10). A subset of 6-OHDA-treated rhesus received daily dosing of pioglitazone (5 mg/kg po; n = 5), a PPARγ agonist with neuroprotective properties. In normal animals, MBP-immunoreactivity (-ir) was identified surrounding approximately 14% of axonal fibers within nerve bundles of the left ventricle, with more myelinated nerve fibers at the base level of the left ventricle than the apex p

Activation of the IκB kinase (IKK) is central to NF-κB signaling. However, the precise activation mechanism by which catalytic IKK subunits gain the ability to induce NF-κB transcriptional activity is not well understood. Here we report a 4 Å x-ray crystal structure of human IKK2 (hIKK2) in its catalytically active conformation. The hIKK2 domain architecture closely resembles that of Xenopus IKK2 (xIKK2). However, whereas inactivated xIKK2 displays a closed dimeric structure, hIKK2 dimers adopt open conformations that permit higher order oligomerization within the crystal. Reversible oligomerization of hIKK2 dimers is observed in solution. Mutagenesis confirms that two of the surfaces that mediate oligomerization within the crystal are also critical for the process of hIKK2 activation in cells. We propose that IKK2 dimers transiently associate with one another through these interaction surfaces to promote trans auto-phosphorylation as part of their mechanism of activation. This structure-based model supports recently published structural data that implicate strand exchange as part of a mechanism for IKK2 activation via trans auto-phosphorylation. Moreover, oligomerization through the interfaces identified in this study and subsequent trans auto-phosphorylation account for the rapid amplification of IKK2 phosphorylation observed even in the absence of any upstream kinase.

Background. We explored decisional conflict as measured with the 16-item Decisional Conflict Scale (DCS) and how it varies across clinical situations, decision types, and exposure to decision support interventions (DESIs). Methods. An exhaustive scoping review was conducted using backward citation searches and keyword searches. Eligible studies were published between 1995 and March 2015, used an original experimental/observational research design, concerned a health-related decision, and provided DCS data. Dyads independently screened titles/abstracts and full texts, and extracted data. We performed narrative syntheses and calculated average or median DCS scores. Results. We included 246 articles reporting on 253 studies. DCS scores ranged from 2.4 to 89.6 out of 100. Highest baseline DCS scores were for care planning (30.5 ± 12.8, median = 30.9) and treatment decisions (30.5 ± 14.6, median = 28.0), in contexts of primary care (33.8 ± 19.8), obstetrics/gynecology (28.8 ± 10.4), and geriatrics (32.6 ± 10.7). Baseline scores were high among decision makers who were ill (29.5 ± 13.8, median = 27.2) or making decisions for themselves (29.7 ± 14.8, median = 26.9). Total DCS scores <25 out of 100 were associated with implementing decisions. Without DESIs, DCS scores tended to increase shortly after decision making (>37.4). After DESI use, DCS scores decreased short-term but increased or remained the same long-term (>6 months). Conclusions. DCS scores were highest at baseline and decreased after decision making. DESIs decreased decisional conflict immediately after decision making. The largest improvements after DESIs were in decision makers who were ill, male, or made decisions for themselves. Meta-analyses focusing on decision types, contexts, and interventions could inform hypotheses about the expected effects of DESIs, the best timing for measurement, and interpretation of DCS scores. [ABSTRACT FROM AUTHOR]

Background. The Decisional Conflict Scale (DCS) measures 5 dimensions of decision making (feeling: uncertain, uninformed, unclear about values, unsupported; ineffective decision making). We examined the use of the DCS over its initial 20 years (1995 to 2015). Methods. We conducted a scoping review with backward citation search in Google Analytics/Web of Science/PubMed, followed by keyword searches in Cochrane Library, PubMed, Ovid MEDLINE, EMBASE, CINAHL, AMED, PsycINFO, PRO-Quest, and Web of Science. Eligible studies were published between 1995 and March 2015, used an original experimental/observational research design, concerned a health-related decision, and provided DCS data (total/subscales). Author dyads independently screened titles, abstracts, full texts, and extracted data. We performed narrative data synthesis. Results. We included 394 articles. DCS use appeared to increase over time. Three hundred nine studies (76%) used the original DCS, and 29 (7%) used subscales only. Most studies used the DCS to evaluate the impact of decision support interventions (n = 238, 59%). The DCS was translated into 13 languages. Most decisions were made by people for themselves (n = 353, 87%), about treatment (n = 225, 55%), or testing (n = 91, 23%). The most common decision contexts were oncology (n = 113, 28%) and primary care (n = 82, 20%). Conclusions. This is the first study to descriptively synthesize characteristics of DCS data. Use of the DCS as an outcome measure for health decision interventions has increased over its 20-year existence, demonstrating its relevance as a decision-making evaluation measure. Most studies failed to report when decisional conflict was measured during the decision-making process, making scores difficult to interpret. Findings from this study will be used to update the DCS user manual. [ABSTRACT FROM AUTHOR]

IκB Kinase (IKK)α is required for activation of an alternative NF-κB signaling pathway based on processing of the NF-κB2/p100 precursor protein, which associates with RelB in the cytoplasm. This pathway, which activates RelB:p52 dimers, is required for induction of several chemokine genes needed for organization of secondary lymphoid organs. We investigated the basis for the 1KKα dependence of the induction of these genes in response to engagement of the lymphotoxin β receptor (LTβR). Using chromatin immunoprecipitation, we found that the promoters of organogenic chemokine genes are recognized by RelB:p52 dimers and not by RelA:p50 dimers, the ubiquitous target for the classical NF-κB signaling pathway. We identified in the IKKα-dependent promoters a novel type of NF-κB-binding site that is preferentially recognized by RelB:p52 dimers. This site links induction of organogenic chemokines and other important regulatory molecules to activation of the alternative pathway. [ABSTRACT FROM AUTHOR]

IκBβ, one of the major IκB proteins, is only partially degraded in response to most extracellular signals. However, the molecular mechanism of this event is unknown. We show here that IκBβ exists in at least two different forms: one that is bound to the NF-κB dimer and the other bound to both NF-κB and κB-Ras, a Ras-like small G protein. Removal of cellular κB-Ras enhances whereas excess κB-Ras blocks induced IκBβ degradation. Remarkably, κB-Ras functions in both GDP- and GTP-bound states, and mutations of the conserved guanine-binding residues of κB-Ras abrogate its ability to block degradation of IκBβ. κB-Ras also directly blocks the in vitro phosphorylation of IκBβ by IKKβ. These observations suggest that IκBβ in the ternary complex is resistant to degradation by most signals. We suggest that specific signals, in addition to those that activate only IKK, are essential for the complete degradation of IκBβ. [ABSTRACT FROM AUTHOR]

We have recently identified an RNA aptamer for the transcription factor NF-κB p50 homodimer [(p50)[sub 2]], which exhibits little sequence resemblance to the consensus DNA target for (p50)[sub 2], but binds (p50)[sub 2] with an affinity similar to that of the optimal DNA target. We describe here the 2.45-Å resolution x-ray crystal structure of the p50 RHR/RNA aptamer complex. The structure reveals that two RNA molecules bind independent of each other to the p50 N-terminal lg-like domains. The RNA secondary structure is comprised of a stem and a stem-loop separated by an internal loop folded into a kinked helix because of the cross-strand stacking of three internal loop guanines. These guanines, placed at the edge of the 3' helix, together with the major groove of the irregular 3' helix, form the binding surface for p50. Each p50 monomer uses the same surface to recognize the distorted RNA major groove as observed in the KB DNA/p50 RHR complex, resulting in strikingly similar interfaces. The structure reveals how the aptamer specifically selects p50 and discriminates against p65. We also discuss the physiological implications of RNA binding by (p50)[sub 2]. [ABSTRACT FROM AUTHOR]