Weight perceptions of parents with children at risk for diabetes

BACKGROUND: The growing epidemic of obesity and diabetes among African American, Latino American, and Native American children in the United States has led to increasing focus on strategies for prevention. However, little is known about the perceptions toward weight, nutrition, and physical activity among these youth. This pilot study explored the perceptions of body weight among overweight and obese children and their parents. RESULTS: Thirty eight children, ages 8-16 years who were enrolled in a diabetes prevention study were surveyed to assess their perception of their weight. Nearly all (84%) of the children were obese. When asked whether they considered themselves to be overweight, African-American children were less likely to report that they were overweight than other children (33% vs. 80% of other children, p = 0.01). The parents of these children (n = 29) were also surveyed to assess their perception of their child's weight. The parents of two-thirds (65%) of the children reported that the child was overweight, while the rest reported their child was underweight or the right weight. African-American parents were less likely to report that their child's weight was unhealthy compared to other parents (46% vs. 77%, p = 0.069). CONCLUSIONS: This study's findings indicate that future intervention efforts should assess children's and parents' awareness of obesity and diabetes risk and these factors should be considered when developing prevention interventions for families with youth at risk for diabetes in underserved communities

A framework for evaluating operations control on a metro line: integrating multiple perspectives and automatically collected train and passenger movement data

Transit operations control, the task of implementing the operations plan in daily operations on a metro line, plays a key role in service delivery because it determines the quality of the service experienced by passengers. Yet, it is one of the most poorly understood aspects of rail transit operations. Faced with a disruption or infeasibility, dispatchers typically choose between several response strategies. However, to date, it has been very difficult to evaluate the positive and negative effects of individual control strategies with respect to operations and passenger travel times under real-world conditions. This paper proposes a framework for the study of rail operations control decisions that integrates automatically collected service and passenger demand data, which are increasingly available and accessible to transit agencies. The framework supports a multiperspective analysis methodology that can inform operational policies and plans, and help operations control decision-makers choose the most appropriate strategies to manage service. By using automatically collected data, taking into consideration the operations control decision environment, and acknowledging that the reliability of the resulting service depends on many factors endogenous to it, this paper takes a distinctly different approach from previous studies, which have relied heavily on modeling, assumed simple operating contexts, and did not consider the full range of available data. Two real-world applications of the framework, where control decisions are evaluated in terms of their operational and passenger impacts, are presented. The methodology is found to be versatile and valuable in providing insights that could not have been gained otherwise. Although the framework is applied to the London Underground, its logic, structure, and procedures are applicable and transferable to other metro systems recognizing that certain specifics would need to be tailored to the available data.Transport for London (Organization

CO17 107. Experiencia inicial con la prótesis de válvula aórtica sin sutura 3f-enable de segunda generación

ObjetivosLa válvula aórtica ATS-3F-Enable™ representa una nueva generación con pericardio equino, stent de nitinol autoexpandible e implantación sin suturas. Evaluamos la técnica de implantación, la seguridad y efectividad de la válvula así como los resultados al año de implantación.Material y métodosAnálisis de resultados en una serie de 27 pacientes consecutivos con estenosis de válvula aórtica y reemplazamiento aislado de la válvula por una ATS-3F-Enable™ entre agosto de 2007 y febrero de 2009. La edad media fue 75,7±6,6 años. Diecisiete mujeres (63%). EuroSCORE mediano: 8, y medio: 7,1±1,7.ResultadosEl tamaño medio de válvula implantada fue de 23mm (franja: 19-27mm). La media de tiempo de clampaje aórtico fue de 39,8±15min (franja: 29-103min). La media de tiempo de circulación extracorpórea fue de 58,6±20min (franja: 41-127). La media de tiempo de hospitalización fue de 11 días (7-22). No hubo mortalidad durante la intervención. Al alta, los gradientes de presión transvalvular medio y alto con ecocardiografía fueron de 11,6 y 18,5mmHg, respectivamente. Dos pacientes presentaron una fuga paravalvular moderada y un paciente fue reoperado a causa de una fuga paravalvular grave. Se requirió la implantación de marcapasos en cinco pacientes (18,5%). El seguimiento al cabo de 1 año fue del 100% y la supervivencia fue del 86%.ConclusionesLa prótesis aórtica ATS-3F-Enable™ puede ser implantada con seguridad y presenta resultados hemodinámicos favorables. El stent autoexpandible y la técnica sin sutura permite una implantación rápida, sin embargo, no tan rápida como esperado. Acumulación de experiencia y algunas modificaciones en el diseño de la prótesis podrán ayudar a perfeccionar la técnica

Simulating the ideal geometrical and biomechanical parameters of the pulmonary autograft to prevent failure in the Ross operation

OBJECTIVES: Reinforcements for the pulmonary autograft (PA) in the Ross operation have been introduced to avoid the drawback of conduit expansion and failure. With the aid of an in silico simulation, the biomechanical boundaries applied to a healthy PA during the operation were studied to tailor the best implant technique to prevent reoperation. METHODS: Follow-up echocardiograms of 66 Ross procedures were reviewed. Changes in the dimensions and geometry of reinforced and non-reinforced PAs were evaluated. Miniroot and subcoronary implantation techniques were used in this series. Mechanical stress tests were performed on 36 human pulmonary and aortic roots explanted from donor hearts. Finite element analysis was applied to obtain high-fidelity simulation under static and dynamic conditions of the biomechanical properties and applied stresses on the PA root and leaflet and the similar components of the native aorta. RESULTS: The non-reinforced group showed increases in the percentages of the mean diameter that were significantly higher than those in the reinforced group at the level of the Valsalva sinuses (3.9%) and the annulus (12.1%). The mechanical simulation confirmed geometrical and dimensional changes detected by clinical imaging and demonstrated the non-linear biomechanical behaviour of the PA anastomosed to the aorta, a stiffer behaviour of the aortic root in relation to the PA and similar qualitative and quantitative behaviours of leaflets of the 2 tissues. The annulus was the most significant constraint to dilation and affected the distribution of stress and strain within the entire complex, with particular strain on the sutured regions. The PA was able to evenly absorb mechanical stresses but was less adaptable to circumferential stresses, potentially explaining its known dilatation tendency over time. CONCLUSIONS: The absence of reinforcement leads to a more marked increase in the diameter of the PA. Preservation of the native geometry of the PA root is crucial; the miniroot technique with external reinforcement is the most suitable strategy in this context

Characterisation of Inactivation Domains and Evolutionary Strata in Human X Chromosome through Markov Segmentation

Markov segmentation is a method of identifying compositionally different subsequences in a given symbolic sequence. We have applied this technique to the DNA sequence of the human X chromosome to analyze its compositional structure. The human X chromosome is known to have acquired DNA through distinct evolutionary events and is believed to be composed of five evolutionary strata. In addition, in female mammals all copies of X chromosome in excess of one are transcriptionally inactivated. The location of a gene is correlated with its ability to undergo inactivation, but correlations between evolutionary strata and inactivation domains are less clear. Our analysis provides an accurate estimate of the location of stratum boundaries and gives a high–resolution map of compositionally different regions on the X chromosome. This leads to the identification of a novel stratum, as well as segments wherein a group of genes either undergo inactivation or escape inactivation in toto. We identify oligomers that appear to be unique to inactivation domains alone

Endothelial Progenitor Cells as Biomarkers of Cardiovascular Pathologies: A Narrative Review

Endothelial progenitor cells (EPC) may influence the integrity and stability of the vascular endothelium. The association of an altered total EPC number and function with cardiovascular diseases (CVD) and risk factors (CVF) was discussed; however, their role and applicability as biomarkers for clinical purposes have not yet been defined. Endothelial dysfunction is one of the key mechanisms in CVD. The assessment of endothelial dysfunction in vivo remains a major challenge, especially for a clinical evaluation of the need for therapeutic interventions or for primary prevention of CVD. One of the main challenges is the heterogeneity of this particular cell population. Endothelial cells (EC) can become senescent, and the majority of circulating endothelial cells (CEC) show evidence of apoptosis or necrosis. There are a few viable CECs that have properties similar to those of an endothelial progenitor cell. To use EPC levels as a biomarker for vascular function and cumulative cardiovascular risk, a correct definition of their phenotype, as well as an update on the clinical application and practicability of current isolation methods, are an urgent priority. Keywords: biomarker; cardiovascular disease; endothelial cells; progenitor

Prevention of neointimal proliferation by immunosuppression in synthetic vascular grafts

Objective: Immunosuppressive agents have been proposed to reduce neointimal hyperplasia in synthetic vascular grafts. Thus, the purpose of the present study was to evaluate the safety and efficacy of rapamycins (systemic vs. local vs. oral administration) and mycophenolate mofetil (MMF) to reduce intimal hyperplasia in infrarenal synthetic vascular grafts of the rat. Methods: Fifty-four Wistar rats (250 g) completed the study after a synthetic vascular graft (ePTFE, Gore-tex, 2 mm diameter, 10 mm length) was implanted end-to-end in the infrarenal aorta. The animals were divided into three groups: group 1 consisted of 12 control animals, group 2 consisted of 37 rats receiving rapamycins, either per os (RAD, 1.5 or 3 mg/kg), intraperitoneally (RPM, 1.5 or 3 mg/kg) or locally (RPM soaking of the graft); and in group 3 (n = 5), MMF (40 mg/kg) was administered orally. The animals were followed weekly with weight controls and signs of toxicity for 30 (n = 37) and 60 (n = 17) days, respectively. All animals were sacrificed and underwent histological examination at completion of the study. Results: All animals survived in groups 1 and 3, but five died in group 2. The weight gain was normal in all groups, except for the subgroup 2a receiving high dose rapamycins orally. All rats in group 3 suffered from diarrhea, whereas animals receiving high dose rapamycins showed toxic signs (hair loss, wound healing problems). Histological examination showed a significant increase in intimal hyperplasia in group 1 (0.03±0.01 and 0.14±0.05 μm after 30 and 60 days, respectively; P < 0.01). Rapamycins in either application or dosage had no significant effect on intimal hyperplasia. Conclusions: Local or systemic administration of rapamycins has no effect on intimal hyperplasia in synthetic vascular grafts. In contrast, toxic signs with weight loss were observed in animals treated with high dose rapamycins, but not in those treated with MMF. Thus, in the rat model, immunosuppresssion with rapamycins or MMF cannot be recommended for the prevention of intimal hyperplasia in the synthetic vascular graft mode