Advances in cell transplantation therapy for diseased myocardium.

The overall objective of cell transplantation is to repopulate postinfarction scar with contractile cells, thus improving systolic function, and to prevent or to regress the remodeling process. Direct implantation of isolated myoblasts, cardiomyocytes, and bone-marrow-derived cells has shown prospect for improved cardiac performance in several animal models and patients suffering from heart failure. However, direct implantation of cultured cells can lead to major cell loss by leakage and cell death, inappropriate integration and proliferation, and cardiac arrhythmia. To resolve these problems an approach using 3-dimensional tissue-engineered cell constructs has been investigated. Cell engineering technology has enabled scaffold-free sheet development including generation of communication between cell graft and host tissue, creation of organized microvascular network, and relatively long-term survival after in vivo transplantation.

A measurement of electrocardiography and photoplethesmography in obese children.

The purpose of this study was to establish heart rate variability normative data on obese children and to comparing the accuracy of two medical technologies photoplethesmography (PPG) with electrocardiography (ECG) while measuring heart rate variability (HRV). PPG is a relatively new technique that holds promise for health care practitioners as an evaluative tool and biofeedback instrument due to its cost and easy administration. This study involved ten children who were recruited for an after-school program designed to reduce obesity. Three-five-minute recordings of HRV were collected while the children were lying in the supine position on a therapy bed. PPG was measured from a thumb sensor and ECG from sensors placed under wristbands on both wrists. The results indicate that PPG is as effective as ECG in measuring the eleven parameters of heart rate variability.

Changes in natriuretic peptides, apelin and adrenomedullin after off-pump and on-pump coronary artery bypass surgery.

AIM: The authors have evaluated the postoperative changes of natriuretic peptides, apelin and adrenomedullin after off-pump (OPCAB) and on-pump coronary artery bypass surgery (CCAB) to assess the impact of these techniques on the myocardium. METHODS: Twenty-two patients underwent OPCAB and 24 patients underwent CCAB. Plasma levels of NT-proANP, NT-proBNP, apelin and adrenomedullin were measured preoperatively, and on the 1st, 3rd, and 5th postoperative day. RESULTS: Natriuretic peptides, apelin and adrenomedullin increased significantly postoperatively. Natriuretic peptides were markedly elevated on the fifth postoperative day. Apelin was still increasing, but adrenomedullin, although elevated, clearly decreased toward baseline levels on the fifth postoperative day. CCAB was associated with significantly higher postoperative cTnI, but levels of natriuretic peptides, adrenomedullin and apelin did not differ significantly after CCAB and OPCAB. cTnI, echocardiographic parameters, cardiac index, and degree of postoperative pericardial effusion did not correlate with levels of natriuretic peptides, apelin and adrenomedullin. Postoperative levels of natriuretic peptides were significantly associated with parameters of renal function, age, and extracardiac arteriopathy. The correlation between preoperative estimated glomerular filtration rate and natriuretic peptides increased along the study intervals (NT-proANP rho: -0.181, -0.350, -0.364, and -0.442; NT-proBNP rho: -0.112, -0.420, -0.405 and -0.550). Also adrenomedullin correlated with parameters of renal function. The postoperative levels of apelin were not associated with any variable. CONCLUSION: A marked, sustained and similar increase in these five markers of cardiac adaptation was detected after OPCAB and CCAB. The upregulation of these peptides should be further investigated to evaluate their potential beneficial/harmful impact on the outcome after coronary surgery.

Need for late lower limb revascularization and major amputation after coronary artery bypass surgery.

OBJECTIVES: The aim of the present study was to estimate the need for late lower limb revascularization and/or major amputation after coronary artery bypass grafting (CABG). DESIGN: Retrospective study. PATIENTS AND METHODS: 1307 residents of Oulu who underwent CABG from 1990 to 2006 formed the basis of this community-wide study. RESULTS: During a mean follow-up of 7.1+/-4.5 years, 111 patients (8.5%) underwent 251 vascular procedures for lower limb ischemia and 25 major amputations. In four patients, revascularization was done for complicated wound after vein graft harvesting. Freedom rates from lower limb revascularization and/or major amputation at 5-, 10- and 15-year were 92.9%, 88.4% and 85.1%, whereas freedom rates from lower limb revascularization for critical ischemia and/or major amputation were 98.1%, 95.2% and 94.7%. Age (p=0.013, HR 1.05), extracardiac arteriopathy (p<0.0001, HR 5.39), left ventricular ejection fraction classes (p=0.03), diabetes (p<0.0001, HR 5.78), and estimated glomerular filtration rate<60mg/min/m(2) (p=0.02, HR 2.22) were independent predictors of lower limb revascularization for critical leg ischemia and/or major amputation. CONCLUSIONS: Patients with extracardiac arteriopathy, diabetes and decreased glomerular filtration rate at the time of CABG are at risk for late lower limb ischemia. These patients would most benefit of a closer follow-up for prevention of peripheral vascular disease and its related complications.

Responses of lipolysis and salivary cortisol to food intake and physical activity in lean and obese children.

This investigation was conducted to determine whether there were differences in lipolytic responses to feeding and physical activity between lean (LN) and obese (OB) children, and if these responses were related to cortisol. Fourteen LN and 11 OB children participated in this study of abdominal lipolysis and salivary cortisol response to breakfast and lunch with an intervening exercise session. Calculated fasting glycerol release was lower in OB than LN (0.645 +/- 0.06 vs. 0.942 +/- 0.11 micromol/ml; P < 0.05). Fasting adipose tissue nutritive flow was lower in OB than in LN subjects, but responses to feeding and exercise were not different. Breakfast elicited a decrease in interstitial glycerol concentration in LN (-33%; P < 0.05), but not in OB (-5%), children, although decreases in glycerol concentration in response to lunch were similar (LN, -41%; OB, -36%). An interaction was evident in the salivary cortisol response to breakfast (LN, no change; OB, increase) and exercise (LN, no change; OB, decrease), but there were no group differences in response to lunch. Alterations in salivary cortisol and lipolysis were not related. These data suggest that salivary cortisol and lipolytic responses are not necessarily linked, but are altered in obesity. Furthermore, prior exercise may improve the antilipolytic response to a meal in OB children.

Diabetic groups as defined by ADA and NDDG criteria have a similar aerobic capacity, blood pressure and body composition. American Diabetes Association and National Diabetes Data Group.

AIMS/HYPOTHESIS: In 1997 the American Diabetes Association (ADA) published new categories for diabetes based on fasting plasma glucose that classified diabetes as a plasma glucose of 7.0 mmol/l, or more, rather than one of 7.8 mmol/l or more, as published previously by the National Diabetes Data Group (NDDG) in 1979. We compared the cardiovascular disease risk factors of subjects classified as having Type II (non-insulin-dependent) diabetes mellitus under the NDDG and ADA criteria. METHODS: We examined a database of approximately 3,700 men (40.4 +/- 11.5 years old) and distributed them into four categories: normal fasting plasma glucose (NFG) of less than 6.1 mmol/l, impaired (IFG) 6.1 to 7.0 mmol/l, ADA diabetic 7.0 to 7.8 mmol/l and NDDG diabetic of 7.8 mmol/l or more. RESULTS: Fasting glucose was 5.2 +/- 0.5, 6.4 +/- 0.2, 7.3 +/- 0.2 and 11.2 +/- 2.9 mmol/l for the subjects of the NFG, IFG, ADA and NDDG groups, respectively. Estimated treadmill VO2max was 41.4 +/- 8.0, 36.0 +/- 7.8, 32.2 +/- 7.6, 30.6 +/- 7.0 ml x kg(-1) x min(-1) in the NFG, IFG, ADA, and NDDG groups, respectively (NFG and IFG > ADA and NDDG: p < 0.05). The ADA and NDDG groups were also similar for resting and exercise blood pressure and body composition. Triglycerides and total: HDL cholesterol ratios were higher and LDL cholesterol concentration was lower, in the NDDG group than in all other groups (p < 0.05). Total and LDL cholesterol in the ADA and NDDG groups were similar. CONCLUSION/INTERPRETATION: The similarities in the aerobic capacities, blood pressure and body composition of the ADA and NDDG groups indicate that the decision to lower the cut-off from 7.8 mmol/l to 7.0 mmol/l blood glucose for the clinical classification of diabetes was appropriate. The ADA and NDDG groups, however, might not have identical risks for cardiovascular disease because of differences between total:HDL cholesterol ratios, circulating HDL cholesterol and triglyceride concentrations.

Modeling the influence of body size on V(O2) peak: effects of model choice and body composition.

This study examined the bivariate relationship between peak oxygen uptake (V(O2) peak); l/min) and body size in adult men (n = 1,314, age 17-66 yr), using both "simple" and "full" iterative nonlinear allometric models. The simple model was described by V(O2) peak = M(b) (or FFM(b)) exp(c SR-PA) exp(a + d age) epsilon (where M is body mass in kg; FFM is fat-free mass in kg; SR-PA is self-reported physical activity; epsilon is a multiplicative error term; and exp indicates natural antilogarithms). The full model was described by V(O2) peak = M(b) (or FFM(b)) exp(c SR-PA) exp(a + d age) + e (epsilon), where e is a permitted Y-intercept term. The M exponent obtained from simple allometry was 0.65 [95% confidence interval (CI), 0.59-0.71], suggestive of a curvilinear relationship constrained to pass through the origin. This "zero Y-intercept" assumption was examined via the full allometric model, which revealed an M exponent of 1.00 (95% CI, 0.7-1.31), together with a positive Y-intercept term (e) of 1.13 (95% CI, 0.54-1.73). The FFM exponents were not significantly different from unity in either the simple or full allometric models. It appears that the curvilinearity of the simple allometric model (using total M) is fictitious and is due to the inappropriate forcing of the regression line through the origin. Utilizing FFM as the body-size variable revealed a linear relationship between body size and V(O2) peak, irrespective of model choice. We conclude that the population mass exponent for V(O2) peak is close to unity.

Renin and hemodynamic responses to exercise in borderline hypertensives.

OBJECTIVE: In this study, we examined the relationship between baseline plasma renin (REN) and hemodynamic variables during recovery from aerobic exercise in 10 Caucasian (C) and 10 African-American (AA) borderline hypertensive females. METHODS: Subjects attended three preliminary sessions and an experimental session in which treadmill walking was performed for 40 minutes at a moderate intensity. During this session, blood was drawn at baseline prior to exercise and immediately following. Blood pressure and other hemodynamic variables were recorded at rest before exercise and for 2 hours afterwards. The average difference from baseline during the two hour recovery period was calculated for each variable and used as the dependent variable in a multiple regression analysis. RESULTS: For mean arterial pressure and cardiac output, the regression slopes did not differ between AA and C. However, during recovery, the average difference from baseline for systemic vascular resistance (SVR) increased in AA but decreased in C. CONCLUSION: In conclusion, REN had a significant effect on SVR but no effect on the other hemodynamic variables during recovery from aerobic exercise. It appears as if the peripheral vasculature in AA may be more sensitive than in C to the vasoconstrictive effects of the renin angiotensin system.

Gait adaptations before and after anterior cruciate ligament reconstruction surgery.

Gait analyses of rehabilitated individuals with anterior cruciate ligament (ACL) deficiency and reconstruction have identified the final adaptations of increased hip extensor torque and hamstring electromyography (EMG) and decreased knee extensor torque and quadriceps EMG during stance. The initial adaptations to injury and surgery are, however, unknown as are the factors that influence the development of the adaptations. Identification of the initial response to injury would provide a basis for determining whether the final adaptations are learned automatically or if they are the result of a lengthy training period in which various factors may affect their development. The purpose of the study was to evaluate the initial effects of ACL injury and reconstruction surgery on joint kinematics, kinetics, and energetics, during walking. Injured limbs from nine subjects with ACL injury were tested 2 wk after injury, and 3 and 5 wk after surgery. Ten healthy subjects were tested. Kinematic and ground reaction data were collected and combined with inverse dynamics to calculate the joint torques and powers. A knee extensor torque throughout most of stance was observed in the injured limbs at all test sessions. This result was in conflict with previous observations of reduced extensor torque or a flexor torque in rehabilitated patients with ACL reconstruction and patients with ACL deficiency. This result also differed from the typical midstance extensor then flexor torque in healthy control subjects. Trend analysis showed a significant (P < 0.001) change in average position at the hip and knee, extensor angular impulse at the hip, and positive work done at the hip 3 wk after surgery followed by a partial rehabilitation at 5 wk after surgery. Power and work produced at the knee were reduced fivefold (P < 0.001) after 5 wk of rehabilitation and did not recover to pre-surgical levels. The existence of a long-lasting knee extensor torque 2 wk after injury indicated that the adaptation process to ACL deficiency is lengthy, requiring many gait cycles, and that numerous factors could be involved in learning the adaptations.

Design and synthesis of 1-heteroaryl-3-(1-benzyl-4-piperidinyl)propan-1-one derivatives as potent, selective acetylcholinesterase inhibitors.

Herein is described the synthesis and structure--activity relationship of a novel series of aromatic and heteroaromatic 3-(1-benzyl-4-piperidinyl)propan-1-one derivatives that display potent and selective inhibition of the enzyme acetylcholinesterase (AChE). 1-(2-Methyl-6-benzothiazolyl)-3-(N-benzyl-4-piperidinyl)propan-1-one hydrochloride, 6d, is one of the most active compounds within this series exhibiting an IC50 for the inhibition of the AChE enzyme equal to 6.8 nM. Compound 6d has shown a dose-dependent elevation of total acetylcholine (ACh) levels in the mouse forebrain with an oral ED50 = 9.8 mg/kg. In addition, in vivo microdialysis experiments in the rat demonstrate that 6d increases extracellular ACh (100% over basal) 1-3 h postdose with an oral ED50 = 4.8 mg/kg.

Lower and upper body anaerobic performance in male and female adolescent athletes.

Little data exist for upper and lower body mechanical power capability of adolescent athletes. This study compared arm (A) and leg (L) anaerobic peak and mean power (PP and MP) of 20 male and 20 female adolescent athletes after normalization for body mass (BM), fat-free mass (FFM), and lean A and L cross-sectional area (CSA). Power outputs were assessed by the Wingate anaerobic test. FFM and CSA were estimated via anthropometry. No significant (P > 0.05) differences existed between the sexes in Tanner sexual maturity, chronological age, or overall training activity. Males had higher (P < 0.001) absolute PP (W) (L 694 vs 442; A 494 vs 309) and MP (L 548 vs 307; A 337 vs 214). Ratio normalization and ANCOVA were used to remove the influence of body size differences. Ratio normalization showed that males had greater leg PP/BM, MP/BM, MP/FFM, MP/CSA, as well as arm PP/BM and MP/BM, whereas all leg and arm PP and MP ANCOVA adjusted means for BM, FFM, and CSA, except arm MP adjusted for FFM, were significantly (P < 0.01) higher for males than females. We conclude that factors other than muscle mass, possibly qualitative in nature, are responsible for the sex difference in anaerobic performance of adolescent athletes.

The relationship between children's perceived and actual motor competence.

To examine the relationship between children's perceived and actual motor competence, 218 children between the ages of 9 and 11 years individually completed the Motor Skill Perceived Competence Scale. After completing the scale, the subject's actual motor competence was measured on a series of gross motor tests. Incomplete principal component analysis identified two actual motor competence dimensions from the motor test battery. The two factors included a lower-body and an upper-body factor of actual motor competence. A two-factor analysis of variance indicated that the boys and girls differed in perceived competence and actual competence. The boys showed higher perceived competence and actual motor competence. In addition, the 9-, 10-, and 11-year-old age groups differed from each other on the lower-body factor of actual motor competence. As age increased, lower-body competence increased. Regression analysis indicated that actual and perceived motor competence was moderately correlated. Adding age to the multiple regression model significantly increased the multiple correlation. Adding gender to the model did not increase the correlation, showing that perceived competence was a function of actual motor competence and age, and this finding held for boys and girls. These findings showed that 9-, 10-, and 11-yr-old children can assess personal motor competence. However, practitioners should attempt to understand children's perceived competence given that their assessments are not extremely accurate.

Transvenous pacing in the presence of acute right ventricular infarction.

Ventricular tachycardia and ventricular fibrillation are very frequent during transvenous pacing in the presence of acute right ventricular infarction. An acceptable pacing threshold is not usually achieved. A relatively high pacing threshold should, therefore, be accepted in these cases with minimum catheter manipulation. Invisible or very small pacing spikes, increased time intervals between the spike and paced QRS, atypical QRS configurations and sensing failure are frequent in these cases.

Complementary colors' effect on closure speed.

Contour closure of complementary colors as figure/ground (measured as RT and correct recognition) was difficult for 20 subjects. Perhaps this involves opponent cells in lateral geniculate nucleus.

Prediction of functional aerobic capacity without exercise testing.

The purpose of this study was to develop functional aerobic capacity prediction models without using exercise tests (N-Ex) and to compare the accuracy with Astrand single-stage submaximal prediction methods. The data of 2,009 subjects (9.7% female) were randomly divided into validation (N = 1,543) and cross-validation (N = 466) samples. The validation sample was used to develop two N-Ex models to estimate VO2peak. Gender, age, body composition, and self-report activity were used to develop two N-Ex prediction models. One model estimated percent fat from skinfolds (N-Ex %fat) and the other used body mass index (N-Ex BMI) to represent body composition. The multiple correlations for the developed models were R = 0.81 (SE = 5.3 ml.kg-1.min-1) and R = 0.78 (SE = 5.6 ml.kg-1.min-1). This accuracy was confirmed when applied to the cross-validation sample. The N-Ex models were more accurate than what was obtained from VO2peak estimated from the Astrand prediction models. The SEs of the Astrand models ranged from 5.5-9.7 ml.kg-1.min-1. The N-Ex models were cross-validated on 59 men on hypertensive medication and 71 men who were found to have a positive exercise ECG. The SEs of the N-Ex models ranged from 4.6-5.4 ml.kg-1.min-1 with these subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Reliability and validity of bioelectrical impedance in determining body composition.

This study was designed to examine the reliability and validity of the bioelectrical impedance method (BIA) of measuring body composition and compare its accuracy with the results obtained by standard anthropometric methods BIA, skinfold fat, and hydrostatically measured percent fat (% fat) were obtained on 44 women and 24 men. Each subject was tested four times by two testers on two different days. Generalizability theory was used to estimate reliability and measurement error that considered both day-to-day and intertester error. The BIA, skinfold fat, and hydrostatic methods were all found to be reliable (Rxx = 0.957-0.987) with standard errors ranging from 0.9 to 1.5% fat. An additional 26 men (n = 50) and 38 women (n = 82) were tested once and combined with the data used for the reliability analysis to cross-validate BIA estimates of % fat with hydrostatically determined % fat. The cross-validation correlations for the BIA determinations of % fat ranged from 0.71 to 0.76, which were significantly lower than that obtained with the sum of seven (sigma 7) skinfolds equations (rxy = 0.92 for men and 0.88 for women). The correlations between the weight-to-height ratio body mass index (BMI) and hydrostatically determined % fat were 0.75 and 0.74 for men and women, respectively. The standard errors of estimate for the two BIA models ranged from 4.6 to 6.4% fat compared with 2.6 and 3.6% fat for the sigma 7 equations. The BIA method for measuring body composition was comparable to the BMI method, with height and weight accounting for most of the variance in the BIA equation.