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Synopsis Stem cell regenerative therapies hold promise for treating diseases across the spectrum of medicine. Recent clinical trials have confirmed the safety of stem cell delivery to the heart with promising but variable results. While significant progress has been made in the preclinical stages, the clinical application of cardiac cell therapy is limited by technical challenges, including inability to isolate a pure population of cardiac-specific progenitors capable of robust engraftment and regeneration, lack of appropriate pre-clinical animal models, uncertainty about the best mode of delivery, paucity of adequate imaging modalities, and lack of knowledge about the fate of transplanted cells. The inability of transplanted cells to structurally and functionally integrate into the host myocardium may pose arrhythmogenic risk to patients. This is in part dependent on the type of cell transplanted, where the expression of gap junctions such as connexin-43 is essential not only for electromechanical integration, but has also been found to be protective against electrical instability post-transplant. Additionally, certain methods of cell delivery, such as intramyocardial injection, carry a higher rate of arrhythmias. Other potential contributors to the arrhythmogenicity of cell transplantation include re-entrant pathways due to heterogeneity in conduction velocities between graft and host as well as graft automaticity. In this paper, we discuss the arrhythmogenic potential of cell delivery to the heart.

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Several previous studies have demonstrated that aged garlic extract (AGE) inhibits the progression of coronary artery calcification and non-calcified plaque (NCP) in the general population. However, its effects on plaque progression in patients with diabetes have not yet been investigated, at least to the best of our knowledge. This study investigated whether AGE reduces the coronary plaque volume measured by cardiac computed tomography angiography (CCTA) in patients with diabetes mellitus (DM). A total of 80 participants with DM with a median age of 57 years were prospectively assigned to consume 2,400 mg AGE/day (after completion, 37 participants) or placebo (after completion, 29 participants) orally. Both groups underwent CCTA at baseline and follow-up 365 days apart. In total, 66 participants completed the study. Coronary plaque volume, including total plaque (TP), dense calcium (DC), fibrous, fibro-fatty and low-attenuation plaque (LAP) volumes were measured based upon pre-defined intensity cutoff values using semi-automated software (QAngio CT). Changes in various plaque types were normalized to the total coronary artery length. The non-parametric Wilcoxon rank-sum test was performed to examine the differences in plaque formation between the 2 groups. No significant differences were found in the baseline characteristics between the AGE and placebo groups. Compared with the placebo group, the AGE group exhibited a statistically significant regression in normalized LAP [median and standard deviation (SD)-0.2 (18.8) vs. 2.5 (69.3), P=0.0415]. No differences were observed in TP, fibrous, or fibrofatty plaque volumes between the AGE and placebo group. On the whole, this study indicated that the %LAP change in the AGE group was significantly greater than that in the placebo group in patients with diabetes. However, further studies are warranted to evaluate whether AGE has the ability to stabilize vulnerable plaque and decrease adverse cardiovascular events.

The success of left ventricular assist device (LVAD) therapy is hampered by complications such as thrombosis and bleeding. Understanding blood flow interactions between the heart and the LVAD might help optimize treatment and decrease complication rates. We hypothesized that LVADs modify shear stresses and blood transit in the left ventricle (LV) by changing flow patterns and that these changes can be characterized using 2D echo color Doppler velocimetry (echo-CDV). We used echo-CDV and custom postprocessing methods to map blood flow inside the LV in patients with ongoing LVAD support (Heartmate II, N = 7). We compared it to healthy controls (N = 20) and patients with dilated cardiomyopathy (DCM, N = 20). We also analyzed intraventricular flow changes during LVAD ramp tests (baseline ± 400 rpm). LVAD support reversed the increase in blood stasis associated with DCM, but it did not reduce intraventricular shear exposure. Within the narrow range studied, the ventricular flow was mostly insensitive to changes in pump speed. Patients with significant aortic insufficiency showed abnormalities in blood stasis and shear indices. Overall, this study suggests that noninvasive flow imaging could potentially be used in combination with standard clinical methods for adjusting LVAD settings to optimize flow transport and minimize stasis on an individual basis.

Given the limited regenerative capacity of the heart, cellular therapy with stem cell-derived cardiac cells could be a potential treatment for patients with heart disease. However, reliable imaging techniques to longitudinally assess engraftment of the transplanted cells are scant. To address this issue, we used ferumoxytol as a labeling agent of human embryonic stem cell-derived cardiac progenitor cells (hESC-CPCs) to facilitate tracking by magnetic resonance imaging (MRI) in a large animal model. Differentiating hESCs were exposed to ferumoxytol at different time points and varying concentrations. We determined that treatment with ferumoxytol at 300 mg/ml on day 0 of cardiac differentiation offered adequate cell viability and signal intensity for MRI detection without compromising further differentiation into definitive cardiac lineages. Labeled hESC-CPCs were transplanted by open surgical methods into the left ventricular free wall of uninjured pig hearts and imaged both ex vivo and in vivo. Comprehensive T 2 *-weighted images were obtained immediately after transplantation and 40 days later before termination. The localization and dispersion of labeled cells could be effectively imaged and tracked at days 0 and 40 by MRI. Thus, under the described conditions, ferumoxytol can be used as a long-term, differentiation-neutral cell-labeling agent to track transplanted hESC-CPCs in vivo using MRI. STEM CELLS TRANSLATIONAL MEDICINE 2016;5:67-74 SIGNIFICANCEThe development of a safe and reproducible in vivo imaging technique to track the fate of transplanted human embryonic stem cell-derived cardiac progenitor cells (hESC-CPCs) is a necessary step to clinical translation. An iron oxide nanoparticle (ferumoxytol)-based approach was used for cell labeling and subsequent in vivo magnetic resonance imaging monitoring of hESC-CPCs transplanted into uninjured pig hearts. The present results demonstrate the use of ferumoxytol labeling and imaging techniques in tracking the location and dispersion of cell grafts, highlighting its utility in future cardiac stem cell therapy trials.

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Manifestações socioculturais que vêm alcançando um grande espaço, atualmente, são as redes sociais e o papel que estas exercem no comportamento das pessoas é cada vez mais preponderante. O objetivo deste trabalho é verificar uma rede social quanto ao padrão de alimentação de usuários e de profissionais de saúde seguidores de perfis fitness. O grupo de estudo foi constituído por 499 usuários seguidores de perfis fitness e 53 nutricionistas. Como ferramenta de coleta de dados, foram elaborados dois questionários distintos: um para cada grupo, contendo perguntas alternativas, fechadas e relacionadas ao tema do estudo. Junto aos usuários seguidores de perfis fitness foi possível verificar os aspectos motivacionais ligados à mudança dos hábitos alimentares. Os resultados permitiram concluir que a grande maioria dos participantes acredita na influência que as postagens exercem nos hábitos da sociedade atual. Postagens fitness no Instagram podem estar relacionadas à incidência de transtornos estético-alimentares, como: anorexia, bulimia, vigorexia e ortorexia. Fotos comparativas parecem direcionar a alimentação, principalmente, para objetivos estéticos, deixando saúde e qualidade de vida em segundo plano. Para se obter um maior sucesso no Instagram, é necessário que profissionais de saúde conheçam melhor o seu público-alvo e reforcem a importância do papel do profissional nas escolhas alimentares. Palavras-chave: Redes Sociais. Instagram. Hábitos Alimentares. Perfis Fitness. AbstractManifestations that haveachieved a great space currently are social networks and the role they play in people's behavior. The objective of this study is to investigate the influence of social network Instagram in the pattern of power users followers of fitness profiles. The study group consisted of 499 followers of  user fitness profiles and 53 nutritionists. As data collection tool two different questionnaires were prepared, one for each group containing alternative questions, and closed related to the study subject. Together with the followers of  profiles fitness it was possible to verify the motivational aspects of changing eating habits. The results allowed to include that the great majority of the participants believe in the influence that the postings exert on the habits of the current society. Posts of physical fitness on Instagram may be related to the incidence of aesthetic eating disorders, such as anorexia, bulimia, vigorexia and orthorexia. Comparative photos seem to direct food mainly for aesthetic purposes, leaving health and quality of life in the background. To achieve greater success on Instagram, health professionals need to better understand their target audience and reinforce the importance of the professional's role in food choices. Keywords: Social Networks. Instagram. Eating Habits. Fitness Profiles.