Faculty Bibliography

Background Transesophageal echocardiography (TEE) is the gold standard for determining mitral regurgitant (MR) leaflet morphology and suitability for edge-to-edge (E2E) repair. Computed tomography (CT) has become essential for evaluation for transcatheter mitral valve replacement (TMVR) and has the temporal and spatial resolution to show leaflet abnormalities with great clarity (figure) but the correlation of findings with TEE has not been well studied. Methods A consecutive series of patients attending clinic for moderate-severe or greater mitral regurgitation underwent CT and TEE. Data was analyzed for leaflet morphology with blinded independent analyses by CT and TEE expert readers. Results A study flow diagram is shown (figure). Mean age was 79.6 (SD 10.9) and mean STS score (repair) was 4.8% (SD3.7). Analyses were independently performed (figure). There was a strong correlation between mitral valve orifice area (MVOA) by CT and TEE (r=0.86, p<0.001), however MVOA was on average 0.45 cm² larger (p=0.003) on CT (5.24cm², SD 1.84) than TEE (4.79cm², SD 1.91). For those cases where CT could make an interpretation on suitability for E2E repair there was 100% concordance between CT and TEE (figure). Conclusion In this preliminary retrospective analysis, a comparison of CT and TEE suggested that CT may be a useful non-invasive modality for the assessment of mitral leaflet morphology and suitability for E2E repair. A prospective comparison is ongoing and will be completed at the time of presentation. [Figure presented]
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Background Computed tomography (CT) has become the standard of care for assessment for the suitability for transcatheter mitral valve replacement (TMVR); however, variation in mitral annular measurements across the cardiac cycle has thus far been poorly studied. Because of this, currently TMVR assessment is cumbersome and involves the assessment of multiple phases. We sought to further understand variation in mitral annular dimensions with the cardiac cycle and assess its potential implications for Methods A total of 118 patients presented to the heart valve clinic and underwent CT for possible TMVR assessment and were consecutively studied with multiphase CT. The mitral annulus was measured in 10 phases using 3mensio mitral planning software and several parameters collected including perimeter, area, anterior-posterior (AP) dimension and commissure-commissure (CC) dimension. Results Of the 118 patients screened, 83.9% had predominant MR, 10.2% mixed MS/MR and 5.9% predominant MS. Changes in perimeter, Area, AP and CC dimensions are shown (figure). Comparison of largest and smallest mean measurements for each phase for perimeter, Area, AP and CC dimensions showed a 2.02%, 4.36%, 8.09% and 2.86% variation respectively. Conclusion In contrast to the dynamism of the aortic annulus and neo-LVOT, the mitral annulus does not vary significantly. This may allow limitation of radiation restricting CT acquisitions to mid-systole where the neo-LVOT is smallest. [Figure presented]
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Uncoupling protein-1 (UCP1) plays a central role in energy dissipation in brown adipose tissue (BAT). Using high-throughput library screening of secreted peptides, we identify two fibroblast growth factors (FGF), FGF6 and FGF9, as potent inducers of UCP1 expression in adipocytes and preadipocytes. Surprisingly, this occurs through a mechanism independent of adipogenesis and involves FGF receptor-3 (FGFR3), prostaglandin-E2 and interaction between estrogen receptor-related alpha, flightless-1 (FLII) and leucine-rich-repeat-(in FLII)-interacting-protein-1 as a regulatory complex for UCP1 transcription. Physiologically, FGF6/9 expression in adipose is upregulated by exercise and cold in mice, and FGF9/FGFR3 expression in human neck fat is significantly associated with UCP1 expression. Loss of FGF9 impairs BAT thermogenesis. In vivo administration of FGF9 increases UCP1 expression and thermogenic capacity. Thus, FGF6 and FGF9 are adipokines that can regulate UCP1 through a transcriptional network that is dissociated from brown adipogenesis, and act to modulate systemic energy metabolism.

Cultured pluripotent cells accumulate detrimental chromatin alterations, including DNA methylation changes at imprinted genes known as loss of imprinting (LOI). Although the occurrence of LOI is considered a stochastic phenomenon, here we document a genetic determinant that segregates mouse pluripotent cells into stable and unstable cell lines. Unstable lines exhibit hypermethylation at Dlk1-Dio3 and other imprinted loci, in addition to impaired developmental potential. Stimulation of demethylases by ascorbic acid prevents LOI and loss of developmental potential. Susceptibility to LOI greatly differs between commonly used mouse strains, which we use to map a causal region on chromosome 13 with quantitative trait locus (QTL) analysis. Our observations identify a strong genetic determinant of locus-specific chromatin abnormalities in pluripotent cells and provide a non-invasive way to suppress them. This highlights the importance of considering genetics in conjunction with culture conditions for assuring the quality of pluripotent cells for biomedical applications.

In sweep rowers, the lower extremities muscle strength translates into the driving force of the boat. Therefore, isokinetic assessment of muscle torque is used by coaches as an indicator of the level of athletes' preparation for competitions. A total of 22 elite sweep rowers performed an isokinetic test of knee joint flexors and extensors, and a test on an asymmetric ergometer with the electromyography measures. Significantly higher quadriceps peak torque was shown during the beginning than the end of the preparatory period (p < 0.05). However, there was no significant knee peak torque difference between the lower extremities (p = 0.398). In the case of the electromyography test of quadriceps, hamstrings and lumbar erector spinae, analysis demonstrated significant bioelectrical activity differences between the sides (p < 0.05). Lower values of quadriceps peak torque at the end of the preparatory period may result from a decrease in the number of power training units during the entire preparatory period. A similar muscle strength between both lower extremities seems to be the correct result in the context of injury prevention. In turn, significant bioelectrical activity differences between the sides possibly are associated with the asymmetric movement pattern in sweep rowers.

OBJECTIVE:=0.02). CONCLUSIONS:In patients with psoriasis, platelets are activated and induce endothelial cell inflammation. Low-dose aspirin improved endothelial cell health in psoriasis via platelet COX-1 inhibition. These data demonstrate a previously unappreciated role of platelets in psoriasis and endothelial cell inflammation, which suggests that aspirin may be effective in improving vascular health in patients with psoriasis. Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT03228017.

Significance: The skin undergoes an inevitable degeneration as an individual ages. As intrinsic and extrinsic factors degrade the structural integrity of the skin, it experiences a critical loss of function and homeostatic stability. Thus, aged skin becomes increasingly susceptible to injury and displays a prolonged healing process. Recent Advances: Several studies have found significant differences during wound healing between younger and older individuals. The hypoxia-inducible factor 1-alpha (HIF-1α) signaling pathway has recently been identified as a major player in wound healing. Hypoxia-inducible factors (HIFs) are pleiotropic key regulators of oxygen homeostasis. HIF-1α is essential to neovascularization through its regulation of cytokines, such as SDF-1α (stromal cell-derived factor 1-alpha) and has been shown to upregulate the expression of genes important for a hypoxic response. Prolyl hydroxylase domain proteins (PHDs) and factor inhibiting HIF effectively block HIF-1α signaling in normoxia through hydroxylation, preventing the signaling cascade from activating, leading to impaired tissue survival. Critical Issues: Aged wounds are a major clinical burden, resisting modern treatment and costing millions in health care each year. At the molecular level, aging has been shown to interfere with PHD regulation, which in turn prevents HIF-1α from activating gene expression, ultimately leading to impaired healing. Other studies have identified loss of function in cells during aging, impeding processes such as angiogenesis. Future Directions: An improved understanding of the regulation of molecular mediators, such as HIF-1α and PHD, will allow for manipulation of the various factors underlying delayed wound healing in the aged. The findings highlighted in this may facilitate the development of potential therapeutic approaches involved in the alteration of cellular dynamics and aging.

Development of curative therapies for chronic hepatitis B virus (HBV) infection will likely require new animal models. Here, we evaluate HBV infection in squirrel monkeys based on the high-sequence homology of the HBV receptor, Na+/taurocholate co-transporting peptide (NTCP), between humans and squirrel monkeys. HBV PreS1 peptide was examined for binding human and squirrel monkey NTCP. Immunodeficient Fah