Reducing the fat content of ground beef in a school foodservice setting

OBJECTIVE

The objective was to develop and test the nutrient results of a two-step defatting procedure with ground beef in a school foodservice setting as part of the Eat Smart school lunch component of the Child and Adolescent Trial for Cardiovascular Health (CATCH).

SETTING AND DESIGN

The procedure was tested in a school foodservice setting to determine the effect of cooking, draining, and subsequent rinsing with hot water on nutrient composition of ground beef. Samples of raw; cooked and drained; and cooked, drained, and rinsed ground beef were collected and chemically analyzed for total fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol, iron, and niacin content.

RESULTS

The results indicated that the total fat and the saturated, monounsaturated, and polyunsaturated fatty acids were significantly reduced 31% to 35% from cooking and draining (P < .005) and reduced by an additional 25% to 30% from rinsing (P < .0001). Cholesterol content was not affected. Iron content increased after the cooking and rinsing, although not significantly. Niacin content significantly decreased during rinsing by 28% (P < .005), but the mean value of the cooked, drained, and rinsed ground beef still met the criteria of the Food and Drug Administration for a good source of niacin.

APPLICATION

The two-step defatting procedure developed for use in a school foodservice setting lowers the total fat and saturated fatty acid content of ground beef without substantially reducing its nutritional quality.

PDGF-BB modulates endothelial proliferation and angiogenesis in vitro via PDGF beta-receptors

To delineate potential angiogenic roles of platelet-derived growth factor (PDGF), we have investigated PDGF and its receptors on bovine aortic endothelial cells that exhibit spontaneous angiogenesis in vitro (angiogenic endothelial cells). Initiation of cord/tube formation by angiogenic endothelial cells required bovine or human serum. Neutralization of PDGF-BB in human serum with a monoclonal anti-PDGF-BB antibody reduced cord/tube formation by 37 +/- 10%, whereas neutralizing anti-PDGF-AA and an IgG isotype-matched control antibody had no effect. DNA synthesis in response to PDGF-BB increased as the cords and tubes developed; furthermore, PDGF-BB induced the incorporation of BrdU in the nuclei of cells associated with these structures. PDGF beta-receptor (PDGF-beta) mRNA increased concomitantly with cord/tube formation, and PDGFR-beta were specifically localized by immunocytochemistry to developing and mature cords and tubes. However, PDGFR-beta transcripts and protein were undetectable in nonangiogenic endothelial cells, and PDGF alpha-receptor mRNA was not expressed in either endothelial cell strain. In contrast to nonangiogenic endothelial cells, angiogenic endothelial cells did not express the PDGF B-chain, the required ligand for the PDGFR-beta. We conclude that (a) PDGF-BB can contribute to angiogenesis in vitro, (b) PDGFR-beta are specific for cord/tube-forming endothelial cells and mediate endothelial proliferation and cord/tube formation, and (c) in angiogenic and nonangiogenic endothelial cells, the expression of PDGFR-beta and PDGF B-chain is inversely correlated. We therefore suggest that paracrine PDGF might amplify angiogenesis via direct action on endothelially expressed PDGFR-beta.

L-type calcium channel activity in human atrial myocytes as influenced by 5-HT

5-Hydroxytryptamine (10 mumol/l; 5-HT) exerted a positive inotropic effect associated with an increase in the Ca2+ current (ICa) in the human right atrium. For detailed analysis, L-type Ca2+ channel currents were recorded from cell-attached patches using 100 mmol/l Ba2+ as charge carrier. Ca2+ channel activity was identified, first, by burst-like inwardly directed currents and, second, by the appearance of long channel openings promoted by Bay K 8644 (1 mumol/l) upon repetitive depolarizations from -80 to 0 mV. The unitary conductance of the Ca2+ channel amounted to 25.8 pS. During superfusion with 5-HT, ensemble averaged (mean) current was enhanced by about 60%. The increase in mean current was brought about by an increase in the channel availability, defined as the ratio of sweeps containing Ca2+ channel activity to the total number of depolarizations. The open probability of a single Ca2+ channel within a sweep with channel activity, unitary conductance, mean open and mean shut times of the channel, however, remained unaffected during superfusion with 5-HT (n = 10). The 5-HT-induced increase in macroscopic ICa in the human atrium can therefore be explained by an enhanced availability of Ca2+ channels to open upon depolarization. The observed changes in gating properties of the human Ca2+ channel by 5-HT are very similar to those which are known from isoprenaline-induced cAMP-dependent phosphorylation of the Ca2+ channel protein in other tissues.

Positive inotropic response to 5-HT in human atrial but not in ventricular heart muscle

The effects of 5-hydroxytryptamine (5-HT) on force of contraction (FC), action potential (AP) and calcium current (ICa) were studied in human right atrial and left ventricular heart muscle. 5-HT exerted a concentration-dependent increase in FC in multicellular atrial preparations; the EC50 was approximately 3 x 10(-7) mol/l. Maximal increases in FC (252 +/- 58% of control values; mean +/- SEM, n = 6) were obtained at 5-HT 10(-5) mol/l. At this concentration, ICa was increased four- to sevenfold in enzymatically isolated atrial myocytes. In contrast, ventricular preparations did not respond to 5-HT; FC, AP and ICa remained unaffected. In the same preparations, FC was increased by isoprenaline three- to fourfold. These results confirm the observation that 5-HT induces a positive inotropic effect in the human atrium, possibly mediated by activation of the adenylyl cyclase - cyclic AMP system. Our study demonstrates, however, the complete lack of functional 5-HT receptors, with respect to changes in FC, in the human ventricle. Since the positive inotropic effect of 5-HT in the human heart is obviously restricted to the atrium, our findings question the concept of developing 5-HT receptor agonists for the treatment of heart failure.

Cardiovascular risk factor assessment of medical students as an educational tool

For three consecutive years, beginning in 1986, we evaluated cardiovascular disease (CVD) risk factors of medical students as part of the teaching program in a Preventive Cardiology Academic Award. Entering students in three consecutive classes were screened on the first day of orientation to medical school. The first year, we evaluated 108 students (71 men and 37 women), the second year, 99 students (75 men, 24 women), and the third year 108 students (67 men and 41 women). During the single four-hour period, we obtained data on personal and family history of CVD risk factors, type A behavior, knowledge of CVD, attitudes toward CVD prevention, measures of depression and anger, blood pressure, blood pressure reactivity, physical activity, and diet. Blood was drawn for lipid analysis. Height and weight were measured, and a physical fitness step test was administered. Pulmonary function was measured during the third year. We used a four-tiered approach to preventive cardiology education. During the assessment session, abnormalities, such as elevated blood pressure or abnormal pulse, were discussed with the student. In the second tier, the data were analyzed and returned to all students during teaching sessions, enabling them to compare their levels with the class and the national averages. For the third tier, students with high-risk values, defined as low-density lipoprotein cholesterol level > or = 150 mg/dL, a total cholesterol or triglyceride level > or = 200 mg/dL, or blood pressure > or = 140/90 mmHg, were seen by faculty physicians who suggested remedial interventions in separate sessions.(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial fibrillation and electrical appliance injury

Electrocardiographic changes and cardiac arrhythmias have been reported frequently in patients suffering high tension (greater than 1,000 V) electrical injuries as well as low tension (less than 350 V) electrical injuries. An association of atrial fibrillation with low tension electrical injury from a household appliance, however, has not been described in the recent literature. We describe a patient with atrial fibrillation induced by a shock from a household toaster. Pathophysiologic mechanisms and approach to treatment are reviewed, emphasizing the transient nature of most electrically induced arrhythmias.

Attendance at health promotion programs: baseline predictors and program outcomes

As part of a family cardiovascular health promotion project, 111 Mexican-American and 95 Anglo-American families with fifth- or sixth-grade children were assigned to either a primary prevention program involving 18 sessions or to a control condition. This article evaluates predictors of attendance at the year long sequence of sessions in the intervention group. In addition it considers the relationship between attendance and program outcomes. Low baseline scores on physical activity and cardiovascular fitness measures were associated with higher attendance for both children and adults. High initial health knowledge and self-motivation were also associated with attendance. Multiple regression analysis showed that adult attendance was significantly predicted by a model including completion of a three-day food record, low exercise, higher socioeconomic status, family adaptability, and self-motivation. Attendance was correlated with greater knowledge gains and larger reductions in blood pressure. The results indicate that motivated families who are in greater need of conditioning attended more sessions in a health promotion program.

Functional role of cholinoceptors and purinoceptors in human isolated atrial and ventricular heart muscle

1. The effects of cholinergic and purinergic stimulation on action potential, force of contraction and 86Rb efflux were investigated in human atrial and ventricular heart muscle. 2. In atrial heart muscle, carbachol and (-)-N6-(R-phenyl-isopropyl)-adenosine (R-PIA) and 5'-(N-ethyl)-carboxamido-adenosine (NECA) evoked transient decreases of action potential duration and force of contraction; the steady-state effects on force of contraction were virtually identical to control values. In the presence of propranolol, steady-state values after carbachol, R-PIA or NECA amounted to about 50% of control values. 3. In ventricular heart muscle, carbachol, NECA and R-PIA did not significantly affect the action potential configuration or force of contraction. 4. Carbachol, NECA and R-PIA induced a maintained depression of the positive inotropic response to isoprenaline in both atrial and ventricular heart muscle. 5. The rate constant of 86Rb efflux was slightly increased by carbachol, NECA and R-PIA in atrial (10-20%) but not in ventricular heart muscle. 6. In the presence of isoprenaline, carbachol, NECA and R-PIA did not significantly affect the rate constant of 86Rb efflux in both atrial and ventricular heart muscle. Isoprenaline alone increased the rate constant of 86Rb by about 25% in both tissues.

Failure of opioids to affect excitation and contraction in isolated ventricular heart muscle

The opioid agonists morphine (selective for mu-receptors) and ethylketocyclazocine (selective for kappa-receptors), at concentrations evoking strong effects in neuronal structures, did not significantly affect the configuration of the intracellularly recorded action potential and the force of contraction in ventricular heart muscle isolated from guinea pigs, rabbits and man. These results suggest that any changes of heart functions in vivo in response to opioid-like drugs are probably not mediated postsynaptically at the myocardial cell membrane but rather presynaptically, influencing the release of noradrenaline and/or acetylcholine from the nerve terminals.

Adrenoceptor-mediated changes of action potential and force of contraction in human isolated ventricular heart muscle

1. The effects of alpha-adrenoceptor stimulation on the action potential and force of contraction were investigated in human isolated ventricular heart muscle and compared with those of beta-adrenoceptor stimulation. 2. The maximal stimulation by isoprenaline of beta-adrenoceptors produced large changes in the force of contraction, which were accompanied by moderate increases in the height of the action potential. The maximal inotropic effect produced by stimulation of alpha-adrenoceptors with phenylephrine, in the presence of propranolol (1 mumol 1(-1)) was much smaller (about 10% of that seen in response to beta-adrenoceptor stimulation), and no significant changes of the action potential configuration were observed. 3. The effects of noradrenaline and adrenaline on the force of contraction were not affected by prazosin. 4. It is concluded that the adrenoceptor-mediated changes of the force of contraction (in the presence of either noradrenaline or adrenaline) in the human ventricle are due virtually exclusively to the stimulation of beta-adrenoceptors.

Assessing knowledge of cardiovascular health-related diet and exercise behaviors in Anglo- and Mexican-Americans

This article describes the Adult and Child Behavior Knowledge Scales that were used as part of the San Diego Family Health Project to measure knowledge of health behaviors related to cardiovascular diseases in two ethnic groups: Anglo- and Mexican-Americans. The psychometric characteristics of these scales indicate acceptable reliabilities for assessing knowledge of dietary sodium, dietary fat, and exercise among both adults and children and differ from other health knowledge scales in that they focus on "behavioral capability" rather than on the link between behavior and disease. It is believed that the type of information measured by our scales is more closely related to behavior changes sought in contemporary cardiovascular disease prevention trials. Results of ANOVA used to test differences in knowledge by ethnicity and sex indicate strong main effects for ethnicity among both children and adults. However, sex was not consistently related to knowledge, except for the general tendency of males to be more knowledgeable about exercise. Step-wise and simultaneous-entry multiple regression were used to test a subset of variables, including sex, education, self-efficacy, acculturation (for Mexican-Americans), and parental health knowledge (for children) as determinants of health knowledge. Education was the strongest predictor for Anglo-American adults, and acculturation level was the strongest for Mexican-American adults. Among children, the only statistically significant variable was parental acculturation level for Mexican-Americans. The scales were found to be useful in measuring differences in knowledge across cultural/linguistic groups and to clearly identify marginally acculturated Mexican-Americans as being least aware of health-behavior knowledge. Implications are discussed.

[Nutritional-physiological effects of dietary fats in rations for growing pigs. 4. Effects of sunflower oil and coconut oil on protein and fat retention, fatty acid pattern of back fat and blood parameters in piglets]

Rations containing 12% sunflower oil (Ration II) and 12% coconut fat (Ration III) were compared with a control ration (Ration I) in a 34 day experiment with growing boars of the German Landrace breed (12-30 kg body weight). The relationships between DP and ME were held constant for all 3 rations, and because of the higher ME contents of the two fat rations, this was achieved by reducing the feed intake, relative to that of the control ration. Parameters measured were growth, composition at slaughter, the apparent digestibility of the crude nutrients and energy, the N-balance and the concentrations of urea, insulin, glucose, triglyceride and cholesterol in the blood. In comparison to Ration I, the apparent digestibilities of crude protein in Rations II and III were 5 and 4% (p less than 0,05) higher, respectively. There was little difference in the apparent digestibility of crude fat between the Rations II and III. However, large differences in the values were determined depending upon method of extraction. There were little differences in the productive performance of the animals fed the fat diets. The control animals had, however, a 13% lower growth rate (p less than 0,05) when compared at similar ME-intakes. As the energy concentration and the growth rate were higher in groups II and III, the feed conversion efficiency and the ME required per kg growth were approximately 30 and 13% lower than that of the control animals. The efficiency of protein utilization of the animals in group III was 4% higher (p greater than 0.05) and the blood urea concentration 20% lower (p less than 0.05) than that in group II. The values for the control animals were intermediate. A similar result was obtained concerning the fat content of the animals. The fat content of the animals in group III was 15.9% and this was significantly lower (p less than 0.001) than that of 21.1% measured in group II. That of the control animals, 18.6%, was not significantly different from the above values. The differences in feeding over the relatively short period of 34 days lead to marked differences in the fatty acid pattern of the backfat. The contents of myristic acid and linoleic acid were significantly different between group II and III; for the former values of 0.8% and 16.9% were determined, respectively, with corresponding values of 48.7 and 11.3% for the latter.(ABSTRACT TRUNCATED AT 400 WORDS)