Mild hypoxic ischaemic encephalopathy and long term neurodevelopmental outcome - A systematic review

AIMS

Hypoxic ischaemic encephalopathy (HIE) remains a significant cause of long term neurodisability despite therapeutic hypothermia (TH). Infants with mild HIE, representing 50% of those with HIE, are perceived as low risk and are currently not eligible for TH [1]. This review examines the available evidence of outcome in term infants with mild HIE.

METHODS

Medline, Embase and Cochrane Clinical Trials databases were searched in March 2017. Studies with well-defined HIE grading at birth and standardised neurodevelopmental assessment at ≥18 months were included. Abnormal outcome was defined as death, cerebral palsy or standardised neurodevelopmental test score more than 1 standard deviation below the mean.

RESULT

Twenty studies were included. Abnormal outcome was reported in 86/341 (25%) of infants. There was insufficient evidence to examine the effect of TH on outcome.

CONCLUSION

A significant proportion of infants with mild HIE have abnormal outcome at follow up.

Steady-state carbamazepine pharmacokinetics following oral and stable-labeled intravenous administration in epilepsy patients: effects of race and sex

Carbamazepine is a widely prescribed antiepileptic drug. Owing to the lack of an intravenous formulation, its absolute bioavailability, absolute clearance, and half-life in patients at steady state have not been determined. We developed an intravenous, stable-labeled (SL) formulation in order to characterize carbamazepine pharmacokinetics in patients. Ninety-two patients received a 100-mg infusion of SL-carbamazepine as part of their morning dose. Blood samples were collected up to 96 hours after drug administration. Plasma drug concentrations were measured with liquid chromatography-mass spectrometry, and concentration-time data were analyzed using a noncompartmental approach. Absolute clearance (l/hr/kg) was significantly lower in men (0.039 ± 0.017) than in women (0.049 ± 0.018; P = 0.007) and in African Americans (0.039 ± 0.017) when compared with Caucasians (0.048 ± 0.018; P = 0.019). Half-life was significantly longer in men than in women as well as in African Americans as compared with Caucasians. The absolute bioavailability was 0.78. Sex and racial differences in clearance may contribute to variable dosing requirements and clinical response.

Glucose and insulin responses to whole grain breakfasts varying in soluble fiber, beta-glucan: a dose response study in obese women with increased risk for insulin resistance

BACKGROUND

A high intake of whole grains containing soluble fiber has been shown to lower glucose and insulin responses in overweight humans and humans with type 2 diabetes.

AIM OF THE STUDY

We investigated the linearity of this response after consumption of 5 breakfast cereal test meals containing wheat and/or barley to provide varying amounts of soluble fiber, beta-glucan (0, 2.5, 5, 7.5 and 10 g).

METHODS

Seventeen normoglycemic, obese women at increased risk for insulin resistance consumed 5 test meals within a randomized cross-over design after consuming controlled diets for 2 days. Blood samples for glucose and insulin response were obtained prior to and 30, 60, 120 and 180 min after consuming the test meals.

RESULTS

Consumption of 10 g of beta-glucan significantly reduced peak glucose response at 30 min and delayed the rate of glucose response. Area under the curve for 2 h-postprandial glycemic response was not affected by beta-glucan content. However, peak and area under the curve of insulin responses were significantly affected by the beta-glucan amount in an inverse linear relationship.

CONCLUSION

These data suggest that acute consumption of 10 g of beta-glucan is able to induce physiologically beneficial effects on postprandial insulin responses in obese women at risk for insulin resistance.

Can dual energy X-ray absorptiometry provide a valid assessment of changes in thigh muscle mass with strength training in older adults?

OBJECTIVE

To determine how dual-energy X-ray absorptiometry (DXA) compares to computed tomography (CT) for measuring changes in total thigh skeletal muscle (SM) mass with strength training (ST) in older adults.

SUBJECTS

Fifty previously sedentary, relatively healthy older men (n=23, 60 (s.d.=7.5) years) and women (n=27, 60 (s.d.=9.3) years).

RESULTS

Results indicate that there was a significant increase in thigh SM mass with ST measured by both CT (3.9+/-0.4%) and DXA (2.9+/-0.6%) methods (both P<0.001), and there was not a significant difference in percent change between the two methods, although there was a substantial absolute difference ( approximately 2 kg) at baseline between the two methods. Although Bland-Altman plots indicate overall agreement between the percent thigh SM mass changes of DXA vs CT methods, the 3.4% error associated with DXA was greater than the thigh SM mass change from DXA. However, the CT measured change in thigh SM mass was greater than its error (0.6%).

CONCLUSIONS

DXA overestimates baseline and after ST thigh SM mass, and may not be able to detect small changes in thigh SM mass with ST due to its higher error. Although DXA has certain advantages that warrant is used in epidemiologic and intervention studies, improvements to DXA are needed for the accurate assessment of small changes in thigh SM mass.

Alpha-actinin-3 (ACTN3) R577X polymorphism influences knee extensor peak power response to strength training in older men and women

BACKGROUND

The alpha-actinin-3 (ACTN3) R577X polymorphism has been associated with muscle power performance in cross-sectional studies.

METHODS

We examined baseline knee extensor concentric peak power (PP) and PP change with approximately 10 weeks of unilateral knee extensor strength training (ST) using air-powered resistance machines in 71 older men (65 [standard deviation = 8] years) and 86 older women (64 [standard deviation = 9] years).

RESULTS

At baseline in women, the XX genotype group had an absolute (same resistance) PP that was higher than the RR (p =.005) and RX genotype groups (p =.02). The women XX group also had a relative (70% of one-repetition maximum [1-RM]) PP that was higher than that in the RR (p =.002) and RX groups (p =.008). No differences in baseline absolute or relative PP were observed between ACTN3 genotype groups in men. In men, absolute PP change with ST in the RR (n = 16) group approached a significantly higher value than in the XX group (n = 9; p =.07). In women, relative PP change with ST in the RR group (n = 16) was higher than in the XX group (n = 17; p =.02).

CONCLUSIONS

The results indicate that the ACTN3 R577X polymorphism influences the response of quadriceps muscle power to ST in older adults.

Use of complementary and alternative medicine for weight control in the United States

OBJECTIVES

The purpose was to assess the prevalence and correlates of complementary and alternative medicine use for weight control.

DESIGN

A list-assisted random-digit-dialed telephone survey of adults was conducted in the fall of 2002 (n = 11,211). The focus of the study was complementary and alternative medicine (CAM) use, other than dietary supplements, in the previous 12 months.

SETTINGS/LOCATION

The sample of respondents was drawn from the total noninstitutionalized U.S. adult population residing in telephone-equipped locations.

SUBJECTS

The sampling procedures were designed to obtain adequate representation of Hispanic and non-Hispanic black respondents. Data from the total sample of 11,211 were weighted to achieve an estimate of the U.S. population. Analyses focused on 372 people who had used CAM within the previous 12 months.

RESULTS

Of the total, 3.3% (n = 372) had used a CAM therapy in the previous 12 months. Higher adjusted odds ratios for CAM use were found among respondents who were exercising for weight control; using a lower carbohydrate, higher protein diet; using a nonprescription weight-loss product(s); overweight; physically active; and not satisfied with one's body (adjusted for age, race, gender, education, and city size). The most often used therapies were yoga (57.4%), meditation (8.2%), acupuncture (7.7%), massage (7.5%), and Eastern martial arts (5.9%). CAM users used CAM therapies on their own (62.6%), in a group setting (26.8%) or with a CAM practitioner (10.6%).

CONCLUSIONS

The use of CAM therapies other than dietary supplements for weight loss was relatively low. The most popular therapy was yoga, and the majority of CAM users used CAM therapies on their own. Persons who had used other weight loss methods had greater odds for using CAM in the previous 12 months, suggesting that CAM use is often added to other weight-loss strategies.

Use of Nonprescription Dietary Supplements for Weight Loss Is Common among Americans

OBJECTIVE

Dietary supplements are not recommended as part of a weight-loss program due to concerns about efficacy and safety. This study sought to assess prevalence and duration of nonprescription weight-loss supplement use, associated weight-control behaviors, discussion of use with a health care professional, and specific ingredient use.

PARTICIPANTS AND DESIGN

Adults aged > or =18 years (n=9,403) completed a cross-sectional population-based telephone survey of health behaviors from September 2002 through December 2002.

STATISTICAL ANALYSES PERFORMED

Both chi2 and t tests were conducted for categorical and mean comparisons and multiple variable logistic regression was used to determine significant predictors.

RESULTS

An estimated 15.2% of adults (women 20.6%, men 9.7%) had ever used a weight-loss supplement and 8.7% had past year use (women 11.3%, men 6.0%); highest use was among women aged 18 to 34 years (16.7%). In regression models, use was equally prevalent among race/ethnic groups and education levels. One in 10 (10.2%) of users reported > or =12 month use, with less frequent long-term use in women (7.7%) than men (15.0%), P=0.01. Almost one third (30.2%) of users discussed use during the past year; 73.8% used a supplement containing a stimulant including ephedra, caffeine, and/or bitter orange.

CONCLUSIONS

Use of supplements for losing weight seems to be common among many segments of the US adult population. Many adults are long-term users and most do not discuss this practice with their physician. Most of the weight-loss supplements taken contain stimulants. Qualified professionals should inquire about use of supplements for weight loss to facilitate discussion about the lack of efficacy data, possible adverse effects, as well as to dispel misinformation that may interfere with sound weight-management practices.

Muscle-power quality: does sex or race affect movement velocity in older adults?

To determine sex and race differences in muscle power per unit of muscle contraction, knee-extensor muscle power normalized for knee-extensor muscle volume was measured in 79 middle-aged and older adults (30 men and 49 women, age range 50-85 years). Results revealed that women displayed a 38% faster peak movement velocity than men and African Americans had a 14% lower peak movement velocity than Whites of a similar age when expressed per unit of involved muscle (p < .001). As expected, men exhibited greater knee-extensor strength and peak power per unit of muscle than women, but women had a faster knee- extension movement velocity per unit of muscle than men at the same relative strength level. Moreover, African Americans had greater knee-extensor muscle volume than Whites but exhibited lower knee-extensor strength and lower movement velocity per unit of muscle when tested at the same relative strength levels.

Availability of weight-loss supplements: Results of an audit of retail outlets in a southeastern city

The sale of nonprescription weight-loss products accounts for millions of dollars spent by Americans trying to lose weight, yet there is little evidence for effectiveness and there are multiple safety concerns. The purpose of this study was to determine what products, and ingredients within products, were available at retail outlets in a metropolitan area. A purposive sampling strategy identified 73 retail outlets. An audit form was used to collect information from product labels. The audit identified 402 products containing 4,053 separate ingredients. The mean number of ingredients per product was 9.9+/-8.96 (range = 1 to 96). A database search was conducted regarding evidence for effectiveness, safety precautions, and side effects for the 10 ingredients that appeared most often across products. Modest evidence of effectiveness exists for green tea (Camellia sinensis), chromium picolinate, and ma huang (Ephedra major). For the remaining seven (ginger root [Zingiber officinale], guarana [Paullinia cupana], hydroxycitric acid [Garcinia cambogia], white willow [Salix alba], Siberian ginseng [Eleutherococcus senticosus], cayenne [Capsicum annuum], and bitter orange/zhi shi [Citrus aurantium]), inadequate or negative evidence exists. Although precautions and contraindications were found for all 10 ingredients, the strongest concerns in the literature appear for ma huang, bitter orange, and guarana. Our audit revealed numerous weight-loss products available to consumers, yet there is little evidence to support the effectiveness of the top 10 ingredients identified and many potential adverse reactions; therefore, food and nutrition professionals should discuss dietary supplement use with their clients.

Effects of moderate-velocity strength training on peak muscle power and movement velocity: do women respond differently than men?

The effects of a 10-wk unilateral knee extension strength training (ST) program on peak power (PP) and peak movement velocity (PV), at given absolute (force load) and relative (same % of 1 repetition maximum) resistances (loads), were examined in 30 older men [64 yr (7 SD)] and 32 older women [62 yr (6 SD)]. PP increased significantly in both men and women at the same absolute ( P < 0.001) and relative loads ( P < 0.01) with ST. Men had a significantly greater increase in relative PP than women with ST at 60% ( P < 0.01) and 70% ( P < 0.001) of 1 repetition maximum when covarying for baseline differences and age. However, when each subject was tested at the same absolute load and when PP was normalized for the muscle volume of the trained knee extensors (i.e., absolute muscle power quality), women increased by 9% ( P < 0.05), whereas men did not change. Both men and women increased their absolute PV ( P < 0.001) but decreased their relative PV significantly with ST ( P < 0.05). However, when baseline values and age were covaried, women had significantly less of a decrease in relative PV quality with ST than men ( P < 0.01), although the difference was small. These normalized data suggest that ST-induced increases in PP depend on muscular hypertrophy in men, but not in women, providing further support for the hypothesis developed from our previous report (Ivey FM, Tracy BL, Lemmer JT, NessAiver M, Metter EJ, Fozard JL and Hurley BF. J Gerontol A Biol Sci Med Sci 55: B152–B157, 2000) that improvements in muscle function with ST result from nonmuscle mass adaptations to a greater extent in women than men.

Vitamin D receptorFokIgenotype influences bone mineral density response to strength training, but not aerobic training

To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT.

Commercial portion-controlled foods in research studies: how accurate are label weights?

OBJECTIVE

The purpose of this study was to evaluate the reliability of label weights as surrogates for actual weights in commercial portion-controlled foods used in a research setting.

DESIGN

Actual weights of replicate samples of 82 portion-controlled food items and 17 discrete units of food from larger packaging were determined over time. Comparison was made to the package label weights for the portion-controlled food items and the per-serving weights for the discrete units.

SETTING

The study was conducted at the US Department of Agriculture's Beltsville Human Nutrition Research Center's Human Study Facility, which houses a metabolic kitchen and human nutrition research facility.

MAIN OUTCOME MEASURES

The primary outcome measures were the actual and label weights of 99 food items consumed by human volunteers during controlled feeding studies. Statistical analyses performed The difference between label and actual weights was tested by the paired t test for those data that complied with the assumptions of normality. The Wilcoxon signed rank test was used for the remainder of the data. Compliance with federal guidelines for packaged weights was also assessed.

RESULTS

There was no statistical difference between actual and label weights for only 37 food items. The actual weights of 15 portion-controlled food items were 1% or more less than label weights, making them potentially out of compliance with federal guidelines.

CONCLUSIONS

With advance planning and continuous monitoring, well-controlled feeding studies could incorporate portion-controlled food items and discrete units, especially beverages and confectionery products. Dietetics professionals should encourage individuals with diabetes and others on strict dietary regimens to check actual weights of portion-controlled products carefully against package weights.

Accuracy of dietary recall using the USDA five-step multiple-pass method in men: an observational validation study

OBJECTIVE

This observational validation study was conducted under controlled conditions to test the accuracy of dietary recall in normal weight, overweight, and obese men using the USDA five-step multiple-pass method for dietary recall.

DESIGN

Cross-sectional analysis of actual and recalled intake of food during 1 day.

SUBJECTS/SETTING

Forty-two men ranging in age from 21 to 65 years and in body mass index from 21 to 39 kg/m(2) who lived in the metropolitan Washington DC area were studied.

INTERVENTION

The subjects selected and consumed all meals and snacks, for 1 day, from a wide variety of foods provided at a human study facility.

MAIN OUTCOME MEASURES

Actual and recalled energy, protein, carbohydrate, and fat intakes were determined by direct observation and by a 24-hour dietary recall, respectively. Dietary recall was determined via telephone administration of the USDA five-step multiple-pass method the following day.

STATISTICAL ANALYSES PERFORMED

Analysis of variance and covariance tested the overall accuracy of recall and the effect of body mass index on dietary recall. Bland-Altman plots were used to assess bias in recall of food intake.

RESULTS

In this population of men, there were no significant differences between actual and recalled intakes of energy (3,294+/-111 and 3,541+/-124 kcal/day), protein (117+/-5 and 126+/-5 g/day), carbohydrate (414+/-16 and 449+/-16 g/day), or fat (136+/-7 and 146+/-8 g/day), respectively. Accuracy of recall was not related to body mass index in that the obese men recalled food intake as accurately as the nonobese men. The energy intake of these men was significantly correlated (r=0.57, P<.05) with their estimated energy requirements. Significant interindividual variation in accuracy of recall was found.

CONCLUSIONS

Under controlled conditions, the USDA five-step multiple-pass method can accurately assess intakes of energy, protein, carbohydrate, and fat in a population of men regardless of their body mass index. Researchers and clinical dietitians need to continue to examine factors that influence underreporting and overreporting of food intake by the multiple-pass 24-hour recall method.

Effectiveness of the US Department of Agriculture 5-step multiple-pass method in assessing food intake in obese and nonobese women

BACKGROUND

National surveys of food intake rely on the 24-h dietary recall method for assessing the nutrient intakes of Americans.

OBJECTIVES

This observational validation study was conducted under controlled conditions to test the effectiveness of the US Department of Agriculture (USDA) 5-step multiple-pass method for dietary recall; to test the ability of normal weight, overweight, and obese women to recall food intake; and to test the accuracy of macronutrient recall.

DESIGN

Women (n = 49) aged 21-65 y with a body mass index (in kg/m(2)) of 20-45 selected all meals and snacks for 1 d from a wide variety of foods. A 24-h dietary recall with the use of the USDA 5-step multiple-pass method was administered by telephone the following day. Analysis of variance and covariance tested the overall accuracy of recall and the effect of BMI on dietary recall.

RESULTS

As a population, the women overestimated their energy and carbohydrate intakes by 8-10%. No significant differences between mean actual and recalled intakes of energy and the macronutrients were observed in the obese women. Normal-weight and overweight women significantly (P < 0.01) overestimated their energy, protein, and carbohydrate intakes. Recalled fat intake was not significantly different from actual intake in women across the BMI range studied.

CONCLUSIONS

The USDA 5-step multiple-pass method effectively assessed mean energy intake within 10% of mean actual intake on the previous day. Obese women more accurately recalled food intake than did overweight and normal-weight women despite undereating on the day of the study.

Variability of total phenytoin serum concentrations within elderly nursing home residents

BACKGROUND

Approximately 6% of all elderly nursing home residents receive phenytoin. Phenytoin concentrations are often measured to guide therapy.

OBJECTIVE

To evaluate the intraresident variability among multiple measurements of total phenytoin serum concentrations in nursing home residents.

METHODS

This was an observational study of 56 elderly (>or=65 years) nursing home residents from 32 nursing homes who had at least 3 phenytoin concentrations measured while on the same dose of phenytoin for at least 4 weeks and who were not taking any interfering concomitant medications. These were a subset of 387 elderly nursing home residents from 112 nursing homes across the United States who had total phenytoin concentration measurements between June 1998 and December 2000.

RESULTS

The mean age was 80.1 years (range, 65 to 100 years) and 58.9% were women. The mean daily dose of phenytoin per resident was 4.9 +/- 1.5 mg/kg. Total phenytoin concentrations within an elderly nursing home resident varied as much as two- to threefold, even though there was no change in dose. The person with the smallest variability had a minimum concentration of 10.0 micro g/mL and a maximum of 10.4 micro g/mL. The person with the largest variability had a minimum concentration of 9.7 micro g/mL and a maximum of 28.8 micro g/mL.

CONCLUSIONS

There is considerable variability in the total phenytoin concentrations in the elderly nursing home resident and measurement of a single total phenytoin concentration should not be used to guide treatment.

AFLP-based assessment of genetic diversity among nine alfalfa germplasms using bulk DNA templates

Improving commercial utilization of perennial Medicago collections requires developing approaches that can rapidly and accurately characterize genetic diversity among large numbers of populations. This study evaluated the potential of using amplified fragment length polymorphism (AFLP) DNA markers, in combination with DNA bulking over multiple genotypes, as a strategy for high-throughput characterization of genetic distances (D) among alfalfa (Medicago sativa L.) accessions. Bulked DNA templates from 30 genotypes within each of nine well-recognized germplasms (African, Chilean, Flemish, Indian, Ladak, Medicago sativa subsp. falcata, Medicago sativa subsp. varia, Peruvian, and Turkistan) were evaluated using 34 primer combinations. A total of 3754 fragments were identified, of which 1541 were polymorphic. The number of polymorphic fragments detected per primer combination ranged from 20 to 85. Pairwise D estimates among the nine germplasms ranged from 0.52 to 1.46 with M. sativa subsp. falcata being the most genetically dissimilar. Unweighted pair-group method arithmetic average (UPGMA) analysis of the marker data produced two main clusters, (i) M. sativa subsp. sativa and M. sativa subsp. varia, and (ii) M. sativa subsp. falcata. Cluster-analysis results and D estimates among the Chilean, Peruvian, Flemish, and M. sativa subsp. varia germplasms supported the hypothesis that Peruvian was more similar to original Spanish introductions into Central and South America than Chilean. Hierarchical arrangement of the nine germplasms was supported by their respective geographic, subspecific, and intersubspecific hybrid origins. Subsets of as few as seven highly informative primer pairs were identified that produced comparable D estimates and similar heirarchical arrangements compared with the complete dataset. The results indicate that use of primer-pair subsets for AFLP analysis of bulk DNA templates could serve as a high-throughput system for accurately characterizing genetic diversity among large numbers of alfalfa populations.

Estimating energy expenditure from the Minnesota Leisure Time Physical Activity and Tecumseh Occupational Activity questionnaires - a doubly labeled water validation

An accurate, simple method for assessing energy expenditure in individuals and in free-living populations continues to be elusive. To compare estimates of energy expenditure (EE) from a combination of two previously validated physical activity questionnaires: Tecumseh Occupational (EE(TEC)) and a 4-wk history version of the Minnesota Leisure Time Physical Activity that included household activities (EE(MNLTPA)) and EE from sleep (EE(SLEEP)), to EE obtained from doubly labeled water (EE(DLW)). We studied free-living males (n = 24) eating a controlled diet designed to maintain body weight and determined EE from doubly labeled water (DLW) during 14 days and EE from physical activity instruments used in epidemiological studies (EE(TEC) and EE(MNLTPA)). There was excellent agreement between EE(DLW) (mean +/- SEM, 13.55 +/- 0.38 MJ/d) and EE(TEC) + EE(MNLTPA) + EE(SLEEP) (EE(TOTAL1)) (13.79 +/- 0.89 MJ/d) with a difference of only 1.0% +/- 5.4%. When the EE from watching TV, reading, and childcare activities was added the total EE (EE(TOTAL2)) (14.87 +/- 0.90 MJ/D) overestimated EE(DLW) by 8.9% +/- 5.4%. Both of these estimates of EE had significant regressions against EE(DLW) (EE(TEC) + EE(MNLTPA) + EE(SLEEP), R(2) = 0.38, P < 0.001; EE(TOTAL2), R(2) = 0.39, P < 0.001). Men whose occupations involved significant intermittent moderate activity had the largest disagreement between EE(DLW) and estimates from the questionnaires. This investigation demonstrates that a combination of previously validated physical activity questionnaires can be used to accurately determine the mean energy expenditure of a population of employed males.

Comparison of energy expenditure estimates from doubly labeled water, a physical activity questionnaire, and physical activity records

BACKGROUND

Various methods are used by epidemiologists to estimate the energy cost of physical activity; these include physical activity records and recalls. However, there is limited validation of these methods against the doubly labeled water technique for determining energy expenditure (EE).

OBJECTIVE

We compared EE as estimated by indirect methods (physical activity records and recall questionnaires) used in epidemiologic studies with EE obtained from doubly labeled water (EE(DLW)) in free-living men.

DESIGN

We determined EE(DLW), energy intake at weight maintenance, and EE from 7-d physical activity records (EE(Record)) and a 7-d physical activity recall questionnaire (EE(Recall)) in 24 men aged 41 plus minus 2.0 y ( plus minus SEM) with a body mass index (in kg/m(2)) of 25.1 plus minus 0.5.

RESULTS

There was excellent agreement between EE(DLW) (13.27 plus minus 0.35 MJ/d) and energy intake (13.19 plus minus 0.36 MJ/d), with a difference of 0.5 plus minus 1.0% ( plus minus SE). The indirect measures of physical activity and EE were 14.17 plus minus 0.37 MJ/d for EE(Record) (difference from EE(DLW): 7.9 plus minus 3.2%) and 17.40 plus minus 1.45 MJ/d for EE(Recall) (difference from EE(DLW): 30.6 plus minus 9.9%).

CONCLUSIONS

Seven-day physical activity records provide an acceptable estimate of EE in free-living adults compared with EE(DLW), but 7-d physical activity recalls have limited application to estimate daily EE. For optimal validity, the 7-d physical activity records require good subject compliance and the provision of careful instructions for their use.

A moderate carbohydrate and fat diet does not impair strength performance in moderately trained males

BACKGROUND

The purpose of this investigation was to study the effects of varied levels of dietary carbohydrate and fat intake on exercise training and high intensity exercise performance in moderately strength trained, aerobic trained and untrained males.

METHODS

Subjects (6 strength trained, 6 aerobically trained serving as an active control group, 6 sedentary) consumed isoenergetic diets considered either high CHO/low fat (HC/LF: total energy 62% CHO, 20% fat, 18% protein) or moderate CHO and fat (MC/MF: total energy 42% CHO, 40% fat, 18% protein) in a randomly assigned crossover design. Each dietary treatment was three weeks in length. Prior to the study and following each dietary treatment, muscular strength and endurance was determined (isokinetic knee extension and flexion, standard concentric free weight bench press).

RESULTS

No differences as a result of the dietary treatment were seen in isokinetic peak torque, total work production, single repetition maximum (1 RM) bench press, or number of bench press repetitions at 80% 1 RM. Self-reported exercise log data showed no dietary effect on the subject's ability to maintain training level.

CONCLUSIONS

These findings indicate that varying dietary macronutrient content (HC/LF or MC/MF) had no effect on exercise training or strength exercise performance in moderately trained (aerobic and strength) or sedentary males.

Dimension and exercise variance in assessment center scores: a large-scale evaluation of multitrait-multimethod studies

This study addresses 3 questions regarding assessment center construct validity: (a) Are assessment center ratings best thought of as reflecting dimension constructs (dimension model), exercises (exercise model), or a combination? (b) To what extent do dimensions or exercises account for variance? (c) Which design characteristics increase dimension variance? To this end, a large set of multitrait-multimethod studies (N = 34) were analyzed, showing that assessment center ratings were best represented (i.e., in terms of fit and admissible solutions) by a model with correlated dimensions and exercises specified as correlated uniquenesses. In this model, dimension variance equals exercise variance. Significantly more dimension variance was found when fewer dimensions were used and when assessors were psychologists. Use of behavioral checklists, a lower dimension-exercise ratio, and similar exercises also increased dimension variance.

Identification and meta-analytic assessment of psychological constructs measured in employment interviews

There has been a growing interest in understanding what constructs are assessed in the employment interview and the properties of those assessments. To address these issues, the authors developed a comprehensive taxonomy of 7 types of constructs that the interview could assess. Analysis of 338 ratings from 47 actual interview studies indicated that basic personality and applied social skills were the most frequently rated constructs in this taxonomy, followed by mental capability and job knowledge and skills. Further analysis suggested that high- and low-structure interviews tend to focus on different constructs. Taking both frequency and validity results into consideration, the findings suggest that at least part of the reason why structured interviews tend to have higher validity is because they focus more on constructs that have a stronger relationship with job performance. Limitations and directions for future research are discussed.

Estimation of energy expenditure from physical activity measures: determinants of accuracy

OBJECTIVE

To describe the determinants, specifically age, body mass index, percentage of body fat, and physical activity (PA) level, associated with over- and underestimation of energy expenditure (EE) using PA records and the Stanford Seven-Day Physical Activity Recall (7DR) compared with doubly labeled water (DLW).

RESEARCH METHODS AND PROCEDURES

We collected PA measures on 24 males eating a controlled diet designed to maintain body weight, and we determined EE from DLW and estimated EE from PA records and 7DR.

RESULTS

Absolute differences in the estimation of EE between DLW and PA assessment methods were greater for the 7DR (30.6 +/- 9.9%) than PA records (7.9 +/- 3.2%). In PA records, overestimation of EE was greater with older age and higher body fatness; EE was overestimated by 16.7% among men 50 years and older compared with only 5.3% among men <40 years of age. For percentage of body fat, EE was overestimated by 19.7% among men with a percentage of body fat > or =30% compared with only 5.6% among men with a percentage of body fat <25%. A trend for less overestimation of EE with higher levels of PA (measured by DLW/basal metabolic rate [BMR]) also was observed in the PA records. In the 7DR, the estimates of EE varied widely and no trends were observed by age, percentage of body fat, and PA levels.

DISCUSSION

Estimation of EE from the 7DR is considerably more variable than from PA records. Factors related to age and percentage of body fat influenced the accuracy of estimated EE in the PA record. Additional studies are needed to understand factors related to accurate reporting of PA behaviors, which are used to estimate EE in free-living adults.

Energy metabolism increases and regional body fat decreases while regional muscle mass is spared in humans climbing Mt. Everest

The objectives of the study were to determine regional changes in body composition, energy expenditure by means of doubly labeled water, and net energy balance during exposure to high and extreme altitudes (5,300-8,848 m). This study focuses on a subset of subjects who consumed the doubly labeled water (three base camp personnel and seven climbers). Regional body composition was determined by measuring skinfold thicknesses and circumferences at 10 different sites on the body. Energy expenditure was measured by doubly labeled water excretion. Discrepancies between actual energy expenditure and data obtained from diet records and body weight changes suggested a chronic underreporting of dietary energy intake, especially by those subjects who reached the highest altitudes. This underreporting may be due in part to diminished cognition or to a preferential focus on survival, rather than on filling out diet records accurately. Mean adjusted dietary intakes were 10.50 +/- 0. 65 MJ/d (2510 +/- 155 kcal/d) for those who remained at base camp, and 20.63 +/- 6.56 MJ/d (4931 +/- 1568 kcal/d) for those who climbed above base camp. Energy expenditure averaged 2.5-3.0 times sea level resting energy expenditure. Differential changes in regional body composition suggested a preferential loss of fat mass and a relative sparing of muscle mass, despite insufficient energy intake to maintain body weight.

Relationship between overnight energy expenditure and BMR measured in a room-sized calorimeter

OBJECTIVE

The purpose of this study was to determine if overnight energy expenditure, the lowest energy expenditure sustained for 60 min during the night, measured and predicted basal metabolic rate are equivalent.

DESIGN

Overnight energy expenditure (ON-EE), the lowest energy expenditure sustained for 60 min during sleep (LS-EE) and basal metabolic rate (BMR) were measured two to seven times in a room-sized indirect calorimeter in 69 adult subjects. Subjects' gender, age, weight and height were also used to predict BMR (FAO/WHO/UNU, 1985) (BMR-WHO).

SETTING

Beltsville Human Nutrition Research Center, Beltsville, MD, USA.

RESULTS

The results from calorimetry measurements (mean +/- s.d.) included: ON-EE (6.87 +/- 0.99 MJ/d), LS-EE (6.18 +/- 0.94 MJ/d) and BMR (6.87 +/- 0.99 MJ/d). Predicted BMR mean was: BMR-WHO, 6.95 +/- 1.03. The mean within-subject difference for the calorimetry measurements were: ON-EE, 0.21 MJ/d; LS-EE, 0.16 MJ/d; and BMR, 0.34 MJ/d. Results indicate there was no significant difference between ON-EE, BMR and BMR-WHO. LS-EE was significantly lower (P < 0.0001) than ON-EE, BMR and BMR-WHO.

CONCLUSION

These results indicate that while metabolic rate drops significantly below BMR during sleep, overnight metabolic rate and BMR are equivalent.

Body composition analysis of small pigs by dual-energy x-ray absorptiometry

We evaluated the use of dual-energy x-ray absorptiometry (DXA) for measuring the gross body composition of small subjects in 97 pigs that ranged from 5 to 27 kg live body weight. Scans were performed using a Lunar DPXL densitometer in the pediatric mode (Version 3.8e). The DXA scans of the live pigs provided measurements of total fat, lean, and bone mineral content. After scanning, the pigs were killed, the entire body was ground, and samples were analyzed chemically (CHEM) for fat, protein, ash, and water content. We found that DXA significantly underestimated the percentage of fat in the body (DXA, 6.9+/-.33% vs CHEM, 10.9+/-.31%, P < .001). The correlation (r) between DXA and chemical measures of percentage fat was .86 and for grams of fat it was .96. Lean tissue mass measured by DXA was highly correlated with CHEM measurements of total grams of body water (r = .99), total grams of body protein (r = .94), and lean body mass (r = .99). The average DXA bone mineral content was within 2% of the amount estimated from total body ash and the correlation between the two values was .94. The relationships between DXA and CHEM measurements for percentages of body composition of pigs that weighed between 5 and 27 kg are described by the following regression equations: %fatCHEM = 5.22 + [.817.fatDXA], (r = .86, standard error of the estimate, SEE = 1.56); %proteinCHEM = -7.8 + [.256%leanDXA], (r = .35, SEE = 2.3); %waterCHEM = -5.2 + [.808-%leanDXA], (r = .59, SEE = 3.67). These results are consistent with previously reported results and suggest that even though direct use of DXA readings may not be sufficiently accurate, the high degree of correlation indicates that with proper calibration the DXA values can be used to predict body composition.

Body composition analysis of pigs from 5 to 97 kg by dual energy X-ray absorptiometry

A total of 231 pigs were anesthetized and then scanned by DXA using a Lunar DPXL instrument. The weight of the pigs ranged from 5 to 97 kg (av. = 37.7 kg). Of the total, 98 pigs were scanned using the pediatric mode and 133 pigs were scanned using the adult mode. After scanning, the pigs were euthanized, the entire body homogenized by grinding, and analyzed chemically for fat, water, protein and total body mineral content. The mean value for the DXA total tissue mass (37.1 kg) was not significantly (P > 0.05, n = 231) different from the mean body weight. The mean DXA value for percent fat was 14.6 and was significantly less (P < 0.05) than the mean value (17.6%) measured by CHEM analysis. The greatest discrepancy occurred in pigs with < 15% body fat. From a prediction equation using the DXA R value [% fat = 493-349(DXA R value)], the DXA estimated percent fat was 18.0%, compared to 17.6% by CHEM analysis (P > 0.05). Using a prediction equation [g protein = -1.062 + 0.22(g DXA lean)], the DXA estimate for body protein content was 17.8%, compared to 17.1% (P < 0.05, n = 131) by CHEM analysis. The DXA estimate for body water content [g water = 508 + 0.74 (g DXA lean)] was 63.8%, compared to 62.6% (P < 0.05, n = 231) by CHEM analysis. The bone mineral content of 83 of the pigs measured by DXA was 2.40%, compared to 2.54% (P < 0.05, n = 83) estimated from CHEM analysis of total body ash [g bone mineral = g total body ash -0.0085(g DXA lean)].

Brief paradoxical sleep deprivation impairs reference, but not working, memory in the radial arm maze task

Selective deprivation of paradoxical sleep after learning results in memory deficits in a variety of tasks. The present experiment was designed to examine the effects of paradoxical sleep deprivation (PSD) upon spatial working and reference memory. Adult male Sprague-Dawley rats were trained for 10 days in an eight-arm radial maze. Food rewards were available in four of the arms, while the other four arms were never baited. After each daily training session, different groups of rats were given 4 h of PSD, beginning either immediately, 4 h, or 8 h after the training experience. An additional group received PSD during the period 13-24 h following daily training. The group that received PSD for 4 h immediately following daily training showed significant impairment compared to the other groups, but the deficit was limited to the reference component of the task. This result suggests that PSD causes deficits only in long-term forms of spatial memory.

Intraabdominal adipose tissue and anthropometric surrogates in African American women with upper- and lower-body obesity

It is well established that visceral adipose tissue (VAT) is associated with increased morbidity and mortality in white women. In a recent study, we found that African American women had smaller depots of VAT. To test the relation of VAT to the commonly used anthropometric surrogates for fat patterning, including waist-to-hip ratio (WHR), waist circumference, subscapular skinfold thickness, and ratio of triceps to subscapular skinfold thickness, we recruited 48 normotensive African American women > 120% of ideal body weight on the basis of WHRs > 0.85 [upper-body obesity (UBO); n = 23] and < 0.76 [lower-body obesity (LBO); n = 25]. There were no differences between groups in age, height, weight, body mass index, or percentage of body fat. VAT was determined by magnetic resonance imaging at L4-5; percentage of fat was determined by dual-energy X-ray absorptiometry. Women with UBO had significantly larger mean (+/- SEM) depots of VAT at L4-5 than did women with LBO (0.26 +/- 0.02 compared with 0.19 +/- 0.02 L). Waist circumference was the single best predictor of VAT at L4-5 in both groups of women whereas WHR was significantly associated with VAT at L4-5 only in women with UBO. In African American women, waist circumference is a better surrogate for VAT than is WHR.

Body composition analysis of chickens by dual energy x-ray absorptiometry

Dual-energy x-ray absorptiometry (DXA) was evaluated as a method for measuring the body composition of growing broiler chickens. A total of 130 chickens, ranging in weight from 400 to 3,290 g, were scanned using a DXA instrument (Lunar DPX-L). Single whole-body scans were acquired and analyzed using pediatric total body research software (neonatal mode) or small animal total body research software (detail or high resolution mode). The DXA measurements provided readings of total tissue mass, percentage fat, fat tissue mass, lean tissue mass, and bone mineral content. After scanning, the bodies of the chickens were frozen, then, after removing the feathers, homogenized for chemical determination of fat, water, and protein content. By chemical analysis, the whole body fat content of the chickens ranged from 2.8 to 27.2%, giving rise to DXA R values (ratio of attenuation coefficients) ranging from 1.415 to 1.339. The accuracy of DXA for measuring total body fat was a function of the scanning program and mode and also the size of the bird. The best agreement between DXA and chemical measurements of percentage body fat were obtained when chickens weighing more than 2,000 g were scanned using either the small animal-detail mode or neonatal mode. None of the scan modes proved to be accurate for measuring the fat content of birds weighing less than 2,000 g. The DXA measurement of lean mass of chickens was found to be highly correlated with both total body protein (R2 = 0.90) and total body water (R2 = 0.93), but was of little value for predicting percentage values for either. The ratio of DXA bone mineral content to total body ash was 0.77; however, the correlation (R2) between the two was only 0.46. These results suggest that although the DXA technique is potentially useful for measuring body composition of chickens, considerable refinement is needed prior to routine application.

AHRA survey: film library practices

Presented here are the highlights of the Film Library Practices Report, taken from the 92-page report published by the AHRA in November 1996. Administrators may find information useful for improving their departments, which function most efficiently with smooth running libraries. The survey of AHRA members covers such topics as staffing, storage, copy policies, PACS and problem areas.

Free-living, 24-hour, and sleeping energy expenditure in sedentary, strength-trained, and endurance-trained men

Fifteen adult male volunteers were assigned to sedentary, moderately strength-trained, and moderately endurance-trained groups (5 per group) to determine the effect of exercise training on energy expenditure (EE). Subjects were matched for age, weight, and height. Group appointments were based on activity questionnaires and American College of Sports Medicine standards. Subjects consumed a mixed diet of 40% fat, 20% protein, and 40% carbohydrate at weight maintenance intake for 3 weeks while continuing their exercise training programs. There was no significant difference between groups for 24-hr EE measured in the controlled environment of a room-sized calorimeter. Free-living EE measured with 2H2(18)O in endurance- and strength-trained groups was significantly higher (19.4% and 35.1%, respectively) than in the sedentary group. Moderate endurance and strength training increased free-living EE but did not affect 24-hr EE when groups followed standardized activity schedules. These results suggest that increased EE caused by moderate exercise training is limited to the energy required to complete the exercise.

Body composition analysis of pigs by dual-energy x-ray absorptiometry

Dual-energy x-ray absorptiometry (DXA) was evaluated as a method for measuring body composition of pigs. Forty-eight female pigs (10.2 to 60.5 kg) were killed and the whole bodies scanned on a DXA instrument. The DXA measurements provided readings of total tissue mass, percentage of fat, fat tissue mass, lean body mass, and bone mineral content. By chemical analysis, the whole body fat content of the pigs ranged from 9.3 to 24.3%, giving rise to DXA RST values (ratio of attenuation coefficients) ranging from 1.386 to 1.334. The average percentage body fat measured by DXA (18.2 +/- .9%) was not significantly different (P = .76) from the results by chemical analysis (17.8 +/- .6%); however, concordance correlation analysis revealed unacceptable accuracy in the DXA measurement due to a negative bias for smaller percentages and a positive bias for larger percentages. Total body fat measured by the two methods was also highly correlated (r = .989), and the average for DXA (7.31 +/- .62 kg) was not significantly different (P = .89) from the value for the chemical method (7.20 +/- .50 kg). The relationship between the DXA estimate of lean body mass and the amount of protein in the body by chemical analysis was described by the equation: kg protein = .227.kg DXA lean -1.28, with a correlation coefficient (r) of .968. The DXA measurements of total tissue mass and actual body weights were highly correlated (r = .999), with an acceptable concordance at the .05 level. Scans were also analyzed for regional composition of the front and back legs. It was generally difficult to determine anatomically how well soft tissue described by DXA regions corresponded to those dissected. The DXA and chemical results for regional analysis of back legs were in better agreement than those for the front legs. These results indicate that DXA may be used as a reliable method for measuring body composition of pigs, but needs more extensive calibration and may be more appropriate for total body rather than regional analysis.

AHRA staff utilization survey measures technologist productivity

The AHRA Staff Utilization Survey is an increasingly valuable reference for administrators trying to increase productivity, maintain patient satisfaction and maintain a reasonable working environment for their employees. This article presents highlights of the full survey, which will be published separately and mailed to all AHRA members in July. The highlights are presented in text, tables and full-color charts.

Energy value of moderate alcohol consumption by humans

We investigated the effects of an equal-energetic substitution of ethanol for dietary carbohydrate in high-and low-fat diets on energy expenditure and body composition. During the controlled feeding study, subjects maintained their weights and consumed only food and drink provided by the US Department of Agriculture Beltsville Human Nutrition Research Center's Diet Study Facility. Subjects (16 men and 32 women) were divided equally into two groups and consumed either a high-or low-fat diet for 16 wk. The feeding period was divided into two 8-wk periods during which either ethanol or carbohydrate was added to the diet (5% of total daily energy intake) in a crossover design. The metabolizable energy content of the diets (with supplements) was determined for all subjects through measurement of total food intake and fecal and urinary losses for 7 d during both 8-wk periods. Energy expenditure, measured for 24 h in a room calorimeter at the end of each 8-wk period, was the same for both periods. Metabolizable energy intake and changes in total-body energy content were used to calculate the total amount of energy expended by each subject for 7 wk during each 8-wk period. Total energy expenditure for 7 wk was the same when subjects consumed either ethanol or carbohydrate. These data clearly show that on an energy basis ethanol and carbohydrate are utilized in the diet with the same efficiency. These data are consistent with the efficiency of use of alcohol for maintenance of metabolizable energy being the same as that for carbohydrate.

AHRA (American Healthcare Radiology Administrators) survey. Trends in radiology 1994: Part I

Departments of medical imaging and therapy must balance the need to improve delivery and efficiency with the need to lower costs by finding better ways to deliver their services. As each department struggles to find its way, new trends will develop. In October, 1994, the AHRA surveyed its membership to determine those trends in hospital and nonhospital facilities. This article presents data and analysis for equipment acquisition and maintenance; operations; staffing and professional coverage; education programs; competition; marketing and new programs. Demographic information and comparisons with AHRA Trends Surveys conducted in 1985, 1987, 1989 and 1991 are included. Editor's Note: Part II of this article will review trends in exam volume, charges and volume from referral sources. Also, data from hospital departments will be analyzed by bed size groupings. Part II will be published in the summer, 1995, issue of Radiology Management, 17(3).

Ethnicity and energy stores

The primary storage form of energy within humans is fat, which accumulates in adipose tissue including the subcutaneous, omental, mesenteric, retroperitoneal, and mammary depots. Although it has been known for some time that the size of these depots varies with sex, age, and physiologic state, it has only recently been suggested that adipose tissue partitioning, and therefore energy storage, may vary among ethnic groups. Indicators of ethnicity include race, place of birth, and culture and traditions. The literature describing energy storage in North American Indians, African Americans, Asian Americans, Mexican Americans, and Pacific Islanders is summarized and data are presented from studies comparing African American and Caucasian (Americans of Northern European descent) obese women. It is proposed that, for the purpose of research, physiologic characteristics and not ethnicity should be the basic factors used to recruit human study volunteers until we obtain mechanisms to discriminate genotype and to relate phenotype to energy storage.

Decreased protein synthesis during dry saturation diving

Changes in metabolism during saturation dives have been reported; however, these changes have not been well defined. This study was conducted to determine the effect of saturation diving on protein metabolism. Whole body protein synthesis was measured by the ammonia and urea endpoint methods, following a single oral dose of 15N-glycine in 11 Navy divers 33.9 +/- 1.9 yr of age. The divers were fed a controlled diet throughout the three trials. Trial I was on the surface, and trials II and III were during dry saturation dives at 0.56 MPa. The protein synthesis results in gram protein per kilogram lean body mass per day, least square mean +/- SD: [formula: see text]. Under the conditions of this series of dry saturation dives, protein synthesis was depressed by up to 30-50% for the urea and ammonia endpoint methods, respectively. An estimate of liver protein synthesis was made by measuring the incorporation of the 15N label into plasma fibrinogen. The 15N enrichment of fibrinogen glycine and the hippurate precursor for fibrinogen were decreased significantly. This dramatic decrease in protein synthesis was observed despite positive nitrogen balance in these divers. Although further investigation is needed to elucidate the mechanism, the decrease in the incorporation of 15N glycine into fibrinogen suggests alteration in liver nitrogen metabolism at 0.56 MPa.

Visceral adipose tissue differences in black and white women

Fat distribution and metabolic variables were studied in 8 black and 10 white age- and weight-matched obese women undergoing a 6-mo weight-reducing regimen. Fat patterning was determined by using anthropometry and computed tomography to quantitate total, subcutaneous, and visceral adipose tissue (VAT) areas at the L2-L3 and L4-L5 levels of the lumbar spine, before, during, and after a modified fast. Black women had smaller depots of VAT than white women at both the L2-L3 (P = 0.004) and L4-L5 (P = 0.054) sites. Differences persisted after an average 17.2-kg weight loss. Although waist-hip ratio was similar in both groups, black women had 23% less VAT than white women (P = 0.007). Black women had significantly lower plasma glucose (P = 0.031) and triglycerides (P = 0.006) with significantly higher plasma high-density-lipoprotein concentrations (P < 0.001). Data from this study suggest that racial differences exist in VAT and metabolic risk factors for obesity-related illness.

AHRA survey. Job content and salary survey. Part III: Chief technologist

In October, 1993, the AHRA surveyed its members on the scope of their jobs, as well as their salaries, benefits and raises. Data was collected on facility demographics, member characteristics, areas of responsibility, volume of procedures performed, number of full-time equivalent (FTE) personnel supervised, and operating budget. The relationship of these factors to salary was investigated. Part I (Radiology Management 16.2, spring, 1994) presented general demographic information and average salary for administrative directors of radiology in hospitals and nonhospitals. Part II (Radiology Management 16.3, summer, 1994) presented information about job content for administrative directors of radiology and compared the results to previous AHRA job content and salary surveys. Part III presents information about demographics, job content and average salary for chief technologists in hospitals and nonhospitals. One hundred and fourteen chief technologists working in hospitals and 16 working in nonhospital facilities responded to the survey. It is important to remember the small number of nonhospital respondents when reviewing the results. Fifty-eight percent of hospital and 56% of nonhospital chief technologists report no change in their benefits package in the past 12 months. Eighty-three percent of respondents from hospitals and 81% from nonhospitals received a salary increase in the past 12 months. The average salary increase was 5% in hospitals and 4% in nonhospitals. Average salary is reported as a function of several variables, which may be interdependent. In hospitals, the average chief technologist's salary is $45,838. In nonhospitals, the average salary is $42,562, 7% lower than for hospitals.

AHRA survey. Part II: Job content and survey comparisons

The AHRA Statistical Resource Committee presents the results of a recent survey of members about their job satisfaction, responsibilities, benefits and salary. Part II includes data and analysis of job content and comparison with prior surveys for administrative directors of radiology. Part III will focus on chief technologists and will be published in the fall issue of Radiology Management.

Job content and salary survey. Part I: Administrative director of radiology

The AHRA Statistical Resource Committee presents the results of a recent survey of members about their job satisfaction, responsibilities, benefits and salaries. Data from the survey is analyzed in text and presented in tables to most accurately portray how administrators are compensated throughout the country. Part II will focus on chief technologists and will be published in the summer issue of Radiology Management.

Energy expenditure and fluid production in hyperbaric He-O2 environments using doubly labeled water

Energy expenditure (EE), carbon dioxide production (rCO2), water turnover (rH2O), and urine production (UP) were measured to determine nutrient requirements of U.S. Navy divers during saturation dives. Parameters were measured in a normal surface environment (n = 10) and in 0.56 MPa (n = 9) and 3.17 MPa (n = 11) helium-oxygen environments. Daily EE, rCO2, and rH2O were measured with the doubly labeled water method for 10-14 days in each environment. Daily UP was determined by 24-h urine collection for 5- to 10-day periods in each environment. Divers consumed a mixed diet composed of 30% calories from fat, 15% protein, and 55% carbohydrate. Both EE and rCO2 increased significantly relative to surface conditions at 0.56 MPa (13 +/- 4% and 11 +/- 4%) and 3.17 MPa (14 +/- 4% and 11 +/- 3%), but there was no difference between dives. Water turnover was not significantly affected by the hyperbaric environment. UP was significantly greater than surface conditions at 0.56 MPa (53 +/- 19%) but not at 3.17 MPa (38 +/- 18%). Increased EE is attributed to thermal stress caused by the helium-oxygen environment. Increased UP may have been caused by decreased evaporative water loss.

AHRA survey. Staff utilization: Part III

Part III is the final installment of the 1993 AHRA membership survey on staff utilization and includes results for radiation therapy, nuclear medicine, interventional/angiography and cardiac catheterization. The information includes the volume of procedures and numbers of FTEs in departmental areas and comparisons with results reported from a similar survey of AHRA members conducted in 1989.