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The Penn State Heart Assistant, a web-based, tablet computer-accessed, secure application was developed to conduct a proof of concept test, targeting patient self-care activities of heart failure patients including daily medication adherence, weight monitoring, and aerobic activity. Patients (n = 12) used the tablet computeraccessed program for 30 days-recording their information and viewing a short educational video. Linear random coefficient models assessed the relationship between weight and time and exercise and time. Good medication adherence (66% reporting taking 75% of prescribed medications) was reported. Group compliance over 30 days for weight and exercise was 84 percent. No persistent weight gain over 30 days, and some indication of weight loss (slope of weight vs time was negative (-0.17; p value = 0.002)), as well as increased exercise (slope of exercise vs time was positive (0.08; p value = 0.04)) was observed. This study suggests that mobile technology is feasible, acceptable, and has potential for cost-effective opportunities to manage heart failure patients safely at home. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study is to examine the effect of pregnancy on final adult height in women whose first live birth occurred in adolescence (

The Millennial Generation, also known as Generation Y, is the demographic cohort following Generation X, and is generally regarded to be composed of those individuals born between 1980 and 2000. They are the first to grow up in an environment where health-related information is widely available by internet, TV and other electronic media, yet we know very little about the scope of their health knowledge. This study was undertaken to quantify two domains of clinically relevant health knowledge: factual content and ability to solve health related questions (application) in nine clinically related medical areas. Study subjects correctly answered, on average, 75% of health application questions but only 54% of health content questions. Since students were better able to correctly answer questions dealing with applications compared to those on factual content contemporary US high school students may not use traditional hierarchical learning models in acquisition of their health knowledge. [ABSTRACT FROM AUTHOR]

Although clinical investigators are regarded as an endangered species, no systematic investigation of the factors that influence doctor participation in clinical research has previously been performed. The objective of this study was to evaluate the influences of selected aspects of medical education, specialty selection and practice type upon current involvement in clinical research. Data were obtained by a mail survey of 428 graduates from the 1985–95 classes of the Penn State College of Medicine. Among the 34% ( n = 145) of doctors who were currently participating in clinical research, there was a higher rate of participation among those in medical and surgical specialties versus those in primary care or hospital-based specialties. Of those participating in clinical research, 46% ( n = 65) had sought external funds for their research, and 82% ( n = 51) of that group had been awarded funds. Those who had been awarded funds as the percentage of their time involved in clinical research increased were more likely to report that research carried out in medical school had positively influenced their current involvement in clinical research ( P = 0.004). The gender distribution among both this latter funded group and the larger group of 145 who were participating in clinical research was 72% men and 28% women, whereas the gender distribution among all respondents was 60% men and 40% women. The 283 individuals who were not participating in clinical research cited financial, family, career plan and practice philosophy as reasons for not doing so. The authors conclude that participation in medical research as a medical student may be under-recognised as a determinant of future involvement in clinical research and that the gender disparity of young doctors entering clinical research must be addressed. [ABSTRACT FROM AUTHOR]

OBJECTIVE:To assess the effect of oral contraceptive (OC) use during adolescence on body composition parameters and cardiovascular disease risk factors.METHODS:We used 9 years of longitudinal data from 66 non-Hispanic white females who were 12 years old at study entry in 1990, and who were subsequently classified either as OC users or nonusers. The OC users (n = 39) used OCs for a minimum of 6 months, were still using at age 21, and had used OCs, on average, for 28 months. The nonusers (n = 27) never used OCs. Individuals who started and then stopped using OCs before age 21 or used OCs for less than 6 months were excluded from these analyses. Cardiolipoprotein profiles were obtained from fasting blood samples (from age 16 to 21), and body composition measurements were made by dual energy x-ray absorptiometry (from age 12.5 to 21). Longitudinal models were used to examine changes in body composition patterns and in cardiolipoprotein patterns.RESULTS:Between ages 12.5 and 21, gains by OC users and nonusers in height, weight, body mass index (BMI), and percent body fat were not significantly different. However, between ages 16 and 21, the OC users had significantly greater increases in total serum cholesterol, serum low-density cholesterol, and serum triglycerides than did the nonusers.CONCLUSION:The use of OCs in young women is associated with less favorable blood lipid patterns, but is not associated with weight gain or increased body fat. The long-term effects of the alteration in the lipid profiles are unknown. [Copyright &y& Elsevier]

ABSTRACT. Objective. To examine how cumulative teenage sports histories and time-averaged teenage calcium intake are related to total body bone mineral gain between ages 12 and 18 years and to proximal femur bone mineral density (BMD) at age 18 years. Design. Longitudinal. Setting. University Hospital and local suburban community in Central Pennsylvania. Study Participants. Eighty-one white females in the ongoing Penn State Young Women's Health Study. Outcome Measures. Total body and proximal femur (hip) bone measurements by dual energy radiograph absorptiometry; nutrient intakes, including calcium, from 33 days of prospective food records collected at regular intervals between ages 12 and 18 years; and self-reported sports-exercise scores between ages 12 and 18 years. Results. Cumulative sports-exercise scores between ages 12 and 18 years were associated with hip BMD at age 18 years (r = .42) but were not related to total body bone mineral gain. Time-averaged daily calcium intake, which ranged from 500 to 1500 mg/day in this cohort was not associated with hip BMD at age 18 years, or with total body bone mineral gain at age 12 through 18 years. Conclusions. The amount of physical activity that distinguishes a primarily sedentary teenager from one who engages in some form of exercise on a nearly daily basis is related to a significant increase in peak hip BMD. Pediatrics 2000;106:40-44; peak hip bone density, teenage sport histories, osteoporosis prevention. [ABSTRACT FROM AUTHOR]

Evaluates the effect of calcium supplementation on bone acquisition in adolescent white girls. Use of 500 mg/d calcium citrate malate; Measurement of bone mineral density and bone mineral content of lumbar spine; Dual-energy x-ray absorptiometry and calcium excretion from 24-hour urine specimens; Increasing daily calcium intake from 80 percent of recommended daily allowance to 110 percent.

The vast majority of peak adult bone mass is accumulated by the time longitudinal growth is complete. As peak bone mass is an important determinant of future fracture risk, the goal of the current calcium recommended dietary allowance during youth is to provide a calcium intake that allows individuals to reach their full genetic potential for acquiring skeletal mass. The advent of controlled trials of calcium supplementation and total body bone mass measurements in children and adolescents provide the first direct way of determining the amount of calcium necessary to achieve optimal skeletal accretion. These studies indicate that the current RDAs are insufficient to support optimal bone mass gain during growth and development. Based on the recent intervention trials, recommendations are made for an RDA of 1250 mg during childhood and 1450 mg during adolescence. These values are consistent with established calcium balance intake thresholds for growth during pre-adolescence and adolescence. [ABSTRACT FROM AUTHOR]

Focuses on the effects of surface chemistry and processing conditions on the adhesive strength of epoxy-based chip attach adhesives on typical leadframe substrates. Experimental approach; Results and discussion of the experiment; Conclusions.

Unlabelled: Incorrectly placed fasciotomy incisions can lead to catastrophic complications in compartment syndrome. Two distinctly different techniques are widely practiced to decompress the anterior and peroneal compartments. In one technique the anterior compartment is decompressed directly, and then the peroneal via the inter-muscular septum, avoiding the peroneal perforators. The second technique relies on surface anatomy landmarks to place the skin incision immediately over the inter-muscular septum, and then the respective fascial envelopes are incised separately. A study in healthy active volunteers was conducted to explore the feasibility of a new technique for the placing the incision very accurately over the inter-muscular septum and so avoiding perforator vessels. Hypothesis The inter-muscular septum can be reliably identified using hand-held ultrasound, and confirmed with MRI.Methods: Fourteen healthy active volunteers underwent hand-held ultrasound to identify the antero-lateral inter-muscular septum in the left lower limb, which was then marked using cod liver oil capsules. The positions of the anterior, septal and peroneal perforators were then identified using hand-held Doppler, and marked in the same way. MRI was then used to measure the relationship between the surface land marks, the septum (compared to its US position), and the relationship of the perforators themselves.Results: Hand held ultrasound was successful in identifying the position of the inter-muscular septum in healthy volunteers, as confirmed on MRI scanning. The position and number of peroneal and anterior perforators proved very variable. Direct decompression of the anterior compartment would result in the loss of all anterior perforators in all subjects. Decompression with the skin incision over the inter-muscular septum would not jeopardise any peroneal muscular perforators.Conclusion: This new technique enables decompression both the anterior and peroneal compartments through an accurately placed incision, sparing the greatest number of perforators. Two brief case histories in which the technique was used are presented. [ABSTRACT FROM AUTHOR]

Richert L, Alexandre E, Lloyd T, Orr S, Viollon-Abadie C, Patel R, Kingston S, Berry D, Dennison A, Heyd B, Mantion G, Jaeck D. Tissue collection, transport and isolation procedures required to optimize human hepatocyte isolation from waste liver surgical resections. A multilaboratory study. Liver International 2004: DOI: 10.1111/j.1478-3231.2004.0930.x. © Blackwell Munksgaard 2004 The European Center for Validation of Alternative Methods (ECVAM) has funded a prevalidation study in three laboratories (France, USA and UK) on the use of human hepatocyte cultures to predict cytochrome P-450 induction. As first stage of this prevalidation study, the purpose of the present work was to set criteria for optimization and harmonization of hepatocyte isolation from human tissue among laboratories to establish a routine procedure. This was achieved by combining and/or comparing the data generated by the two independent European laboratories (France and UK). The results confirmed that surgical waste material is a valuable source for obtaining high quality hepatocytes under certain pre-, intra- and post-operative conditions: cell yield of viable hepatocytes was not significantly affected by age and sex of patients, nor indications for resection, steatosis or cholestasis. Cold ischeamia up to 5 hours did not influence viable cell yield allowing transport of material. The use of biopsy sizes between 50–100 g, cannulation with 2–4 cannulae, digestion with collagenase-containing digestion medium at a flow rate of 25 ml/cannula for 20 minutes, with cut surface being glued in order to reform Glisson's capsule, should optimize the total yield of viable human hepatocytes obtained per preparation of waste liver surgical resecitons. [ABSTRACT FROM AUTHOR]

We analyzed the prevalence of anti-mitochondrial autoantibodies (AMA) in adult- and juvenile-onset myositis longitudinal cohorts and investigated phenotypic differences in myositis patients with AMA. We screened sera from myositis patients including 619 adult- and 371 juvenile-onset dermatomyositis (DM, JDM), polymyositis (PM, JPM), inclusion body myositis (IBM), or amyopathic DM patients and from healthy controls, including 164 adults and 92 children, for AMA by ELISA. Clinical characteristics were compared between myositis patients with and without AMA. AMA were present in 5% of adult myositis patients (16 of 216 DM, 10 of 222 PM, 4 of 140 IBM, 1 of 19 amyopathic DM), 1% of juvenile myositis patients (3 of 302 JDM, 1 of 25 JPM), and 1% of both adult and juvenile healthy controls. In patients with adult-onset myositis, AMA were associated with persistent muscle weakness, Raynaud's phenomenon, dysphagia, and cardiomyopathy. Adult myositis patients with AMA may have more severe or treatment refractory disease, as they more frequently received glucocorticoids and intravenous immunoglobulin. In juvenile myositis, children with AMA often had falling episodes and dysphagia, but no other clinical features or medications were significantly associated with AMA. AMA are present in 5% of adult myositis patients and associated with cardiomyopathy, dysphagia, and other signs of severe disease. The prevalence of AMA is not increased in patients with juvenile myositis compared to age-matched healthy controls. Our data suggest that the presence of AMA in adult myositis patients should prompt screening for cardiac and swallowing involvement. Key Points • Approximately 5% of a large North American cohort of adult myositis patients have anti-mitochondrial autoantibodies. • Adults with anti-mitochondrial autoantibodies often have chronic weakness, Raynaud's, dysphagia, cardiomyopathy, and more severe disease. • Anti-mitochondrial autoantibodies are rare in juvenile myositis and not associated with a specific clinical phenotype. [ABSTRACT FROM AUTHOR]

Aims: To illustrate the practical and technical challenges along with the safety aspects when performing MRI‐guided electrophysiological procedures in a pre‐existing diagnostic magnetic resonance imaging (MRI) environment. Methods and Results: A dedicated, well‐trained multidisciplinary interventional cardiac MRI team (iCMR team), consisting of electrophysiologists, imaging cardiologists, radiologists, anaesthesiologists, MRI physicists, electrophysiological (EP) and MRI technicians, biomedical engineers, and medical instrumentation technologists is a prerequisite for a safe and feasible implementation of CMR‐guided electrophysiological procedures (iCMR) in a pre‐existing MRI environment. A formal dry run "mock‐up" to address the entire spectrum of technical, logistic, and safety issues was performed before obtaining final approval of the Board of Directors. With this process we showed feasibility of our workflow, safety protocol, and bailout procedures during iCMR outside the conventional EP lab. The practical aspects of performing iCMR procedures in a pre‐existing MRI environment were addressed and solidified. Finally, the influence on neighbouring MRI scanners was evaluated, showing no interference. Conclusion: Transforming a pre‐existing diagnostic MRI environment into an iCMR suite is feasible and safe. However, performing iCMR procedures outside the conventional fluoroscopic lab, poses challenges with technical, practical, and safety aspects that need to be addressed by a dedicated multi‐disciplinary iCMR team. [ABSTRACT FROM AUTHOR]

This study investigated the radiofrequency-induced heating due to interventional catheters at 1,5 T magnetic resonance image (MRI) based on a combined modeling and experimental method. Two types of interventional catheters, a “single wire” and a “dual wire” catheter, were studied. They were modeled inside a high-resolution anatomical human model along four trajectories. In total, 4 insertion depths, from 17.5 to 70 cm, and 13 scanning landmarks were studied to cover various clinically relevant scenarios. The computational model for the catheters was based on a transfer function approach, measured using the reciprocity theorem. Results of the study showed that the upper limit of the temperature rises near the catheter tip may reach up to 100 °C when scaled to the 2 W/kg average whole-body specific absorption rate (SAR). The computational model was validated experimentally by measuring the induced heating near the catheter in a gel-filled phantom. The data showed a good agreement between the result obtained by the combined method and the direct measurement method with a difference of less than 1 °C. The results suggest that the proposed combined approach, based on the transfer function method, may accurately and efficiently predict the temperature rises near ablation catheters at 1,5 T MRI exposure. [ABSTRACT FROM AUTHOR]

Goal: This study aims at a systematic assessment of five computational models of a birdcage coil for magnetic resonance imaging (MRI) with respect to accuracy and computational cost. Methods : The models were implemented using the same geometrical model and numerical algorithm, but different driving methods (i.e., coil “defeaturing”). The defeatured models were labeled as: specific (S2), generic (G32, G16), and hybrid (H16, \H16fr\text{-forced}). The accuracy of the models was evaluated using the “symmetric mean absolute percentage error” (“SMAPE”), by comparison with measurements in terms of frequency response, as well as electric ( \\vec E\) and magnetic ( \ \vec B \) field magnitude. Results: All the models computed the \ \vec B \ within 35% of the measurements, only the S2, G32, and H16 were able to accurately model the \\vec E\ inside the phantom with a maximum SMAPE of 16%. Outside the phantom, only the S2 showed a SMAPE lower than 11%. Conclusions: Results showed that assessing the accuracy of \ \vec B \ based only on comparison along the central longitudinal line of the coil can be misleading. Generic or hybrid coils — when properly modeling the currents along the rings/rungs — were sufficient to accurately reproduce the fields inside a phantom while a specific model was needed to accurately model \\vec E\ in the space between coil and phantom. Significance: Computational modeling of birdcage body coils is extensively used in the evaluation of radiofrequency-induced heating during MRI. Experimental validation of numerical models is needed to determine if a model is an accurate representation of a physical coil. [ABSTRACT FROM AUTHOR]

Abstract: To render a diagnosis pediatricians rely upon reference standards for bone mineral density or bone mineral content, which are based on cross-sectional data from a relatively small sample of children. These standards are unable to adequately represent growth in a diverse pediatric population. Thus, the goal of this study was to develop sex and site-specific standards for BMC using longitudinal data collected from four international sites in Canada and the United States. Data from four studies were combined; Saskatchewan Paediatric Bone Mineral Accrual Study (n =251), UBC Healthy Bones Study (n =382); Penn State Young Women''s Health Study (n =112) and Stanford''s Bone Mineral Accretion study (n =423). Males and females (8 to 25 years) were measured for whole body (WB), total proximal femur (PF), femoral neck (FN) and lumbar spine (LS) BMC (g). Data were analyzed using random effects models. Bland–Altman was used to investigate agreement between predicted and actual data. Age, height, weight and ethnicity independently predicted BMC accrual across sites (P <0.05). Compared to White males, Asian males had 31.8 (6.8) g less WB BMC accrual; Hispanic 75.4 (28.2) g less BMC accrual; Blacks 82.8 (26.3) g more BMC accrual with confounders of age, height and weight controlled. We report similar findings for the PF and FN. Models for females for all sites were similar with age, height and weight as independent significant predictors of BMC accrual (P <0.05). We provide a tool to calculate a child''s BMC Z-score, accounting for age, size, sex and ethnicity. In conclusion, when interpreting BMC in pediatrics we recommend standards that are sex, age, size and ethnic specific. [Copyright &y& Elsevier]

We used 10 years of longitudinal data from Penn State Young Women''s Health Study to explore predictors of adult bone structural geometry and strength. One hundred twelve participants were enrolled in the study at age 12. We report findings on the 76 participants who remained in the study for 10 years. Measurements were recorded biannually for the first 4 years and annually thereafter. Proximal femur DXA scans (Hologic QDR 2000) were taken from 17–22 years and analyzed using a hip structure analysis program to assess areal bone mineral density (BMD, g/cm2), subperiosteal width, cortical thickness, bone cross-sectional area (CSA), and section modulus (Z) at the narrow neck and femoral shaft. Total body lean mass (g) was measured with DXA total body scans. Nutrition, anthropometry, and sex steroids [testosterone (T) and estradiol (E2)] were measured from ages 12–22 years. Multiple regression models were used to assess predictors of change in bone variables (17–22 years) and absolute bone values (average of age 21 and 22 years, n = 79). Neck Z (+3.1%) and width (+1.3%), but not BMD (-0.8%), increased significantly from age 17 to 22 years. At the shaft, all variables increased (+1.0–4.0%, P < 0.01). After controlling for baseline (age 17) height, weight and bone measurement, weight change (neck) or lean mass (shaft), and age of menarche were the primary predictors of change in bone strength. After controlling for height and weight, only lean mass predicted absolute young adult Z at both the neck (r2 = 0.48, P < 0.01) and the shaft (r2 = 0.67, P < 0.01). When lean mass was removed from the model, sports exercise score replaced lean mass as a predictor of Z at both neck (r2 = 0.40, P < 0.01) and shaft (r2 = 0.60, P < 0.01) sites. For neck and shaft cortical thickness and BMD, both estradiol and sports score/lean mass were positive predictors (r2 = 0.15–0.40, P < 0.01). For neck bone width, testosterone levels (negative) and lean mass (positive) were significant (r2 = 0.48). Results were similar for each geometric variable at the shaft site. These data suggest that bone adapts its bending strength primarily to mechanical loading (represented by lean mass and sports exercise score) and that sex steroids are associated with bone geometric structure. [Copyright &y& Elsevier]

Abstract: Extramedullary haematopoiesis (EMH) is a rare disorder and is characterised by the appearance of haemopoietic tissue outside of the bone marrow. The most common of the previously recognised sites of EMH are the spleen and the liver. This case-report describes a unique case of pelvic EMH secondary to herditary spherocytosis with regression of the lesion following splenectomy. Current principles of managing EMH are also discussed. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of oral contraceptive (OC) use during adolescence on body composition parameters and cardiovascular disease risk factors.Methods: We used 9 years of longitudinal data from 66 non-Hispanic white females who were 12 years old at study entry in 1990, and who were subsequently classified either as OC users or nonusers. The OC users (n = 39) used OCs for a minimum of 6 months, were still using at age 21, and had used OCs, on average, for 28 months. The nonusers (n = 27) never used OCs. Individuals who started and then stopped using OCs before age 21 or used OCs for less than 6 months were excluded from these analyses. Cardiolipoprotein profiles were obtained from fasting blood samples (from age 16 to 21), and body composition measurements were made by dual energy x-ray absorptiometry (from age 12.5 to 21). Longitudinal models were used to examine changes in body composition patterns and in cardiolipoprotein patterns.Results: Between ages 12.5 and 21, gains by OC users and nonusers in height, weight, body mass index (BMI), and percent body fat were not significantly different. However, between ages 16 and 21, the OC users had significantly greater increases in total serum cholesterol, serum low-density cholesterol, and serum triglycerides than did the nonusers.Conclusion: The use of OCs in young women is associated with less favorable blood lipid patterns, but is not associated with weight gain or increased body fat. The long-term effects of the alteration in the lipid profiles are unknown. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Interactive real-time mapping and ablation of the pulmonary veins and cavotricuspid isthmus in an ovine model with an externally-irrigated MRI-compatible ablation catheter," by Suchi Grover and colleagues is presented.

An abstract of the conference paper "Interactive real-time mapping and ablation of the pulmonary veins and cavotricuspid isthmus in an ovine model with an externally-irrigated MRIcompatible ablation catheter," by Anand N. Ganesan and colleagues is presented.