bluuebunny/crossref_metadata_2025 huggingface dataset:
The Accumulation of Visceral Adipose Tissue may be Influenced by Intra‐Abdominal Temperature
Authors: Kahn Henry S.
Published: September 2012

Despite the established link between visceral obesity and major chronic diseases, little is known about physiologic factors that directly and specifically lead to the accumulation of visceral fat. I hypothesize that reduced intra‐abdominal temperature might be a physical factor underlying the partitioning of adipose tissue to the intra‐abdominal region rather than the periphery. The hypothesis is supported by biochemical reports that rat and bovine lipoprotein lipase have increased activity when incubated at lower temperatures. Persons exercising in cool water have been found to preserve subcutaneous fat whereas comparable exercise without local cooling results in subcutaneous fat loss. Pima Indians, a group that commonly acquires extreme levels of visceral fat, have been found to have lower intraabdominal temperatures during sleep than weight‐matched European‐Americans. In a study of four young men and four young women, I have noted that mean intra‐abdominal basal temperatures were higher for women than men (36.51 ± 0.18°C vs. 35.91 ± 0.11°C; p = .0014). Since the men are more likely to acquire visceral obesity at later age, this also provides support for my hypothesis. Investigators might wish to examine further the temperature dependence of adipose‐tissue lipoprotein lipase, the temperature variation between sites of adipose tissue, and the effects of foods, physical activities, smoking and drugs on localized body temperature.
Comparison of Attitudes and Behaviors Related to Nutrition, Body Size, Dieting, and Hunger in Russian, Black‐American, and White‐American Adolescents
Authors: Stevens June , Alexandrov A.A. , Smirnova S.G. , Deev A.D. , Gershunskaya Yu. B. , Davis C.E. , Thomas Ratna
Published: September 2012

Attitudes and behaviors related to nutrition are known to differ between white‐American and black‐American adolescents, however, little is known about teenagers from Russia. We hypothesized that, compared with white‐American or black‐American teenagers, Russian teenagers would prefer a larger body size, be less likely to diet, and be less concerned about being overweight. Self‐administered questionnaires were completed by 196 students in Moscow, 326 white‐American, and 239 black‐American adolescents who attended school in North Carolina (mean age = 16). Ideal body mass index (BMI) was calculated from measured height and the response to the question, “What do you consider to be your ideal weight?” Mean ideal BMI was higher in black‐American boys (25.1) and girls (21.4) than in white‐American boys (22.1) and girls (19.2), and Russian boys (21.8) and girls (19.1). After controlling for BMI, black‐American girls were less than half as likely to report dieting compared with white‐American girls. There were no significant differences among white‐American girls and Russian girls, and there were no ethnic differences between boys in the prevalence of dieting. White‐American girls and black‐American girls were much more likely to identify being overweight as an important nutritional concern than were Russian girls (odds ratios >10), and there were no ethnic differences among boys. We conclude that preferences for body size, the prevalence of dieting, and concerns about being overweight were similar in Russian and white‐American teens, with the exception of Russian teenaged girls who were less likely than American girls to identify being overweight as an important concern. Overall, weight‐related attitudes and behaviors in Russian teenagers were more similar to those of white‐American teenagers than those of black‐American teenagers.
Serial Measurements of Body Composition in Obese Subjects During a Very‐Low‐Energy Diet (VLED) Comparing Bioelectrical Impedance with Hydrodensitometry
Authors: Rodgers Carol D. , Anderson David , Gossain Ved V. , Carella Michael J.
Published: September 2012

Bioelectrical impedance analysis (BIA) is a convenient, inexpensive, and noninvasive technique for measuring body composition. BIA has been strongly correlated with total body water (TBW) and also has been validated against hydrodensitometry (HD). The accuracy and clinical utility of BIA and HD during periods of substantial weight loss remain controversial. We measured body composition in moderately and severely obese patients serially using both methods during a very‐low‐energy diet (VLED). Mean initial weight in these patients was 116 (± 30) kg (range, 74–196 kg). Mean weight loss was 24 (± 13) kg with a decrease in fat mass (FM) by HD of 20 kg (p<0.001) and a decrease in fat‐free mass (FFM) of 3.6 kg (p<0.05). Loss of FFM is best predicted by the rate (kg/wk) of weight loss (r2 = 0.86, p<0.0001). FFM, as predicted from BIA equations, was highly correlated with FFM as estimated by HD during all testing sessions (r=0.92‐0.98). Although highly correlated, BIA overestimated FFM relative to HD and this difference appeared to be more pronounced for taller patients with greater truncal obesity. Although the discrepancy was no greater during weight‐loss treatment, the level of disagreement was considerable. Therefore, the two methods cannot be used interchangeably to monitor relative changes in body composition in patients with obesity during treatment with VLED. The discrepancy between BIA and HD may be caused by body mass distribution considerations and by perturbations in TBW which affect the hydration quotient for FFM (BIA) and/or which affect the density constants for FFM and FM (HD).
Eating or Drinking Elicited by Direct Adrenergic or Cholinergic Stimulation of Hypothalamus
Authors: Grossman S.P.
Published: September 2012

A double cannula system, allowing repeated stimulation of central structures with crystalline chemicals, was developed. This technique was employed to study the effects of adrenergic and cholinergic stimulation of the lateral hypothalamus of rats. Drug‐specific effects on the feeding and drinking mechanisms, respectively, were observed.
Prediction Equations Do Not Eliminate Systematic Error in Self‐Reported Body Mass Index
Authors: Plankey Michael W. , Stevens June , Fiegal Katherine M. , Rust Philip F.
Published: September 2012

PLANKEY MICHAEL W, JUNE STEVENS, KATHERINE M FLEGAL, PHILIP F RUST. Prediction equations do not eliminate systematic error in self‐reported body mass index.

Epidemiological studies of the risks of obesity often use body mass index (BMI) calculated from self‐reported height and weight. The purpose of this study was to examine the pattern of reporting error associated with self‐reported values of BMI and to evaluate the extent to which linear regression models predict measured BMI from self‐reported data and whether these models could compensate for this reporting error. We examined measured and self‐reported weight and height on 5079 adults aged 30 years to 64 years from the second National Health and Nutrition Examination Survey. Measured and self‐reported BMI (kg/m2) was calculated, and multiple linear regression techniques were used to predict measured BMI from self‐reported BMI. The error in self‐reported BMI (self‐reported BMI minus measured BMI) was not constant but varied systematically with BMI. The correlation between measured BMI and the error in self‐reported BMI was −0.37 for men and −0.38 for women. The pattern of reporting error was only weakly associated with self‐reported BMI, with the correlation being 0.05 for men and −0.001 for women. Error in predicted BMI (predicted BMI minus measured BMI) also varied systematically with measured BMI, but less consistently with self‐reported BMI. More complex models only slightly improved the ability to predict measured BMI compared with self‐reported BMI alone. None of the equations were able to eliminate the systematic reporting error in determining measured BMI values from self‐reported data. The characteristic pattern of error associated with self‐reported BMI is difficult or impossible to correct by the use of linear regression models.
Physical Activity and Physical Fitness in African‐American Girls With and Without Obesity
Authors: Ward Dianne S. , Trost Stewart G. , Felton Gwen , Saunders Ruth , Parsons Mary Ann , Dowda Marsha , Pate Russell R.
Published: September 2012

Abstrac

WARD, DIANNE S, STEWART G TROST, GWEN FELTON, RUTH SAUNDERS, MARY ANN PARSONS, MARSHA DOWDA, RUSSELL R PATE. Physical activity and physical fitness in African‐American girls with and without obesity.

Lack of physical activity and low levels of physical fitness are thought to be contributing factors to the high prevalence of obesity in African‐American girls. To examine this hypothesis, we compared habitual physical activity and physical fitness in 54 African‐American girls with obesity and 96 African‐American girls without obesity residing in rural South Carolina. Participation in vigorous (6 METs) (VPA) or moderate and vigorous physical activity (4 METs) (MVPA) was assessed on three consecutive days using the Previous Day Physical Activity Recall. Cardiorespiratory fitness was assessed using the PWC 170 cycle ergometer test. Upper body strength was determined at two sites via isometric cable tensiometer tests. Relative to their counterparts without obesity, girls with obesity reported significantly fewer 30‐minute blocks of VPA (0. 90 ± 0. 14 vs. 1. 3 ± 0. 14) and MVPA (1. 2 ± 0. 18 vs. 1. 7 ± 0. 16) (p<0. 01). Within the entire sample, VPA and MVPA were inversely associated with body mass index (r=−0. 17 and r=−0. 19) and triceps skinfold thickness (r=−0. 19 and r=−0. 22) (p<0. 05). In the PWC 170 test and isometric strength tests, girls with obesity demonstrated absolute scores that were similar to, or greater than, those of girls without obesity; however, when scores were expressed relative to bodyweight, girls with obesity demonstrated significantly lower values (p<0. 05). The results support the hypothesis that lack of physical activity and low physical fitness are important contributing factors in the development and/or maintenance of obesity in African‐American girls.
How NOT to Approach the Obesity Problem
Authors: Flatt J. P.
Published: September 2012

FLATT, JP. How NOT to approach the obesity problem.

The emphasis given to the energy balance equation has fostered the widespread belief that obesity is a problem of energy balance. This mistaken view has led to many unjustified and unfortunate interpretations, because obesity is, rather, a problem of the interaction between body composition and food intake regulation.
Archeology of Mind—Obesity and Psychoanalysis
Authors: Bray George A.
Published: September 2012

“To tell us that every Species of Things is endow'd with an occult specifick Quality by which it acts and produces manifest effects is to tell us nothing: But to derive two or three general Principles of Motion from Phenomena, and afterwards to tell us how the Properties and Actions of all corporeal Things follow from those manifest Principles, would be a very great step in Philosophy, though the Causes of these Principles were not yet discover'd.”
Effects of Intracerebroventricular Infusion of Leptin in Obese Zucker Rats
Authors: Al‐Barazanji Kamal A. , Buckingham Robin E. , Arch Jonathan R.S. , Haynes Andrea , Mossakowska Danuta E. , McBay Diane L. , Holmes Stephen D. , McHale Mark T. , Wang Xin‐Min , Gloger Israel S.
Published: September 2012

AL‐BARAZANJI, KAMAL A, ROBIN E BUCKINGHAM, JONATHAN RS ARCH, ANDREA HAYNES, DANUTA E MOSSAKOWSKA, DIANE L McBAY, STEPHEN D HOLMES, MARK T McHALE, XIN‐MIN WANG, ISRAEL S GLOGER. Effects of intracerebro‐ventricular infusion of leptin in obese Zucker rats.

The obese Zucker rat (OZR) exhibits a missense mutation in the cDNA for the leptin receptor, producing a single amino acid substitution in the extracellular domain of the receptor. A mutation in the leptin receptor gene of the db/db mouse prevents the synthesis of the long splice variant of the receptor. The possibility that the OZR, like the db/db mouse, is refractory to the actions of murine leptin was tested by infusing the protein intracerebroventricularly via a minipump for 7 days. Lean Zucker rats (LZR) infused with leptin acted as positive controls, and other groups of OZR and LZR were infused with vehicle. In LZR, leptin reduced body‐weight and food intake and increased brown adipose tissue (BAT) temperature. Plasma corticosterone increased (61%) in these rats, and plasma triglycerides fell (78%). Leptin treatment improved tolerance to an oral glucose load (16% reduction in the area under the blood glucose curve) while lowering plasma insulin. In OZR, the actions of leptin were blunted. Food intake was slightly, but not significantly, reduced. Although there was a reduction in the rate of increase in body mass, the effect of leptin was about half that seen in LZR. BAT temperature and glucose tolerance were unchanged. In contrast to the elevated plasma corticosterone seen in

LZR, leptin reduced the level of this hormone (27%) in OZR. In OZR and LZR treated with leptin, the plasma leptin levels were increased 24‐fold and 47‐fold, respectively. The results suggest that leptin retains some efficacy in OZR, although these rats are less responsive than LZR.
The Influence of Anatomical Boundaries, Age, and Sex on the Assessment of Abdominal Visceral Fat
Authors: Clasey Jody L. , Bouchard Claude , Wideman Laurie , Kanaley Jill , Teates C. David , Thorner Michael O. , Hartman Mark L. , Weltman Arthur
Published: September 2012

CLASEY, JODY L, CLAUDE BOUCHARD, LAURIE WIDEMAN, JILL KANALEY, C DAVID TEATES, MICHAEL O THORNER, MARK L HARTMAN, ARTHUR WELTMAN. The influence of anatomical boundaries, age, and sex on the assessment of abdominal visceral fat.

Single‐slice abdominal computed tomography (CT) scanning has been used extensively for the measurement of abdominal visceral fat (AYF). Optimal anatomical scan location and pixel density ranges have been proposed and are specifically reported to allow for the replication and standardization of AVF measurements. Standardization of the anatomical boundaries for CT measurement of AVF and the influence of age and gender on results obtained with different boundary locations have received much less attention. To determine the influence of three boundary analysis methods (AVF‐1, AVF‐2, and AVF‐3) on the measurement of AVF by CT, 54 older (60 years to 79 years) and 37 younger (20 years to 29 years) healthy men and women were examined. The measurement boundary for AVF‐1 was the internal most aspect of the abdominal and oblique muscle walls, and the posterior aspect of the vertebral body. AVF‐2 used fat measurements enclosed in a boundary formed by the midpoint of the abdominal and oblique muscle walls, and the most posterior aspect of the spinous process. AVF‐3 used fat measurements enclosed in a boundary formed by the external border of the abdominal and oblique muscle walls, and the external border of the erector spinae. Greater AVF measures were obtained with AVF‐2 and AVF‐3 compared with AVF‐1 (p<0.0001). These differences were greater in older compared with younger subjects (p<0.0001) and greater in women compared with men (p<0.02). The significantly greater AVF measurements obtained with AVF‐2 and AVF‐3 resulted from the inclusion of larger amounts of fat that are not drained by the portal circulation. This included retroperitoneal, intermuscular, and intramuscular lipid droplets, which increase with aging. On the basis of these results, we recommend the AVF‐1 anatomical boundaries for the measurement of AVF in clinical investigations, particularly with older subjects. These data demonstrate the importance of precise and reproducible anatomical boundaries for the measurement of AVF, particularly in longitudinal studies.
Assessment of Socially Acceptable Body Sizes by University Students
Authors: Rand Colleen S. W. , Resnick Jaquelyn L. , Seldmant Roberta S.
Published: September 2012

RAND, COLLEEN SW, JAQUELYN L RESNICK, ROBERTA S SELDMAN. Assessment of socially acceptable body sizes by university students.

The objective of this study was to determine if more than one body size (the ideal) is considered socially acceptable. Two hundred undergraduates rated ideal male and female sizes, all socially acceptable male and female sizes, and their own current and desired sizes. Stimuli were arrays of nine outline drawings illustrating extremely thin to very fat male and female sizes. Most students considered three of nine sizes socially acceptable. There was high consensus on the sizes considered ideal. Although nearly three‐quarters of women and half of men desired to be a different size, most considered their current size socially acceptable for other people. The results clearly demonstrate the existence of a range of socially acceptable male and female body sizes. The current size of most students was within this range. Exclusive focus on ideal body size distorts understanding of both other‐size and own‐size evaluations.
Leptin and the Development of Obesity and Diabetes in Psammomys obesus
Authors: Collier Greg R. , Walder Ken , Lewandowski Paul , Sanigorski Andrew , Zimmetf Paul
Published: September 2012

COLLIER, GREG R, KEN WALDER, PAUL LEWAN DOWSJCI, ANDREW SANIGORSKI, PAUL ZIMMET. Leptin and the development of obesity and diabetes in Psammomys obesus.

The recently discovered ob gene and its circulating product, leptin, may be critical factors in the control of energy balance. Recent studies in ob/ob mice, which lack circulating leptin, have shown dramatic reductions in food intake and bodyweight after leptin treatment. In addition, studies in both humans with obesity and animal models of obesity have demonstrated hyperleptinemia. Here, we report a longitudinal study examining changes in circulating leptin during the development of obesity and diabetes in Psammomys obesus. Over the 8 weeks of the study, lean animals increased their bodyweight by 154% and leptin levels remained essentially unchanged. In contrast, animals that developed obesity (223 % increase in bodyweight), hyperglycemia, and hyperinsulinemia also developed hyperleptinemia between 4 weeks and 8 weeks of age. These results demonstrate that the development of hyperleptinemia is associated with the development of obesity and subsequent metabolic abnormalities.
The Effect of Dehydroepiandrosterone Combined with a Low‐Fat Diet in Spontaneously Obese Dogs: A Clinical Trial
Authors: Kurzman Ilene D. , Panciera David L. , Miller James B. , MacEwen E. Gregory
Published: September 2012

Dehydroepiandrosterone (DHEA) has been shown to have antiobesity activity in rodents and spontaneously obese dogs. This study evaluated the effect of DHEA or placebo combined with a low‐fat/high‐fiber diet in spontaneously obese dogs in a clinical trial. Spontaneously obese, euthyroid dogs, referred to the University of Wisconsin School of Veterinary Medicine for treatment of their obesity, were evaluated for percent overweight, rate of weight loss, serum cholesterol, plasma lipoprotein and serum biochemistry profiles, complete blood count, and endocrine profiles (T4, T3, Cortisol, insulin, and DHEA‐sulfate). DHEA‐treated dogs had a significantly increased rate of actual and percent excess weight loss compared with placebo‐treated dogs. Serum cholesterol decreased in both treatment groups; however, DHEA‐treated dogs had a significantly greater reduction than placebo‐treated dogs. DHEA‐treated dogs had a significant 32% reduction in total plasma cholesterol, which was due to a 27% reduction in the lipoprotein fraction containing the high‐density lipoprotein (HDL) and a 50% reduction in the lipoprotein fraction containing the low‐density lipoprotein (LDL). Placebo‐treated dogs did not have a significant reduction in total plasma cholesterol or in the fraction containing LDL; however, they did have a significant 11% reduction in the fraction containing HDL. Significant decreases in serum T4 and T3 observed in dogs receiving DHEA were not noted in dogs receiving placebo. DHEA in combination with caloric restriction results in a faster rate of weight loss than does caloric restriction alone. In addition, DHEA has hypocholesterolemic activity, particularly affecting the lipoprotein fraction containing the LDL cholesterol.
Evidence for Multiple Determinants of the Body Mass Index: The National Heart, Lung, and Blood Institute Family Heart Study
Authors: Borecki Ingrid B. , Higgins Millicent , Schreiner Pamela J. , Arnett Donna K. , Mayer‐Davis Elizabeth , Hunt Steven C. , Province Michael A.
Published: September 2012

The body mass index (BMI) is a complex phenotype representing the amount of fat mass, lean mass, body build and proportions, and it is likely to be affected by various metabolic processes, hormonal effects, energy intake and expenditure, and interactions within and among these broad categories of etiologic factors. Nonetheless, several previous studies have reported evidence for major gene segregation for the BMI in various populations. Data on a random sample of Caucasian families participating in the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study were analyzed to document the extent of familial resemblance and to investigate whether a similar monogenic inheritance pattern could be detected. Genetic analysis was carried out on age‐ and sex‐adjusted BMI values. Familial correlations were significant implying a maximal heritability, including all genetic and environmentally inherited additive factors, of 41% to 59%. Segregation analysis revealed the presence of two maximum likelihood solutions, one characterized as a recessive Mendelian gene and the other as a major effect with an ambiguous transmission pattern. The presence of two such solutions is consistent with detection of two separate factors, each influencing the BMI distribution in a substantive manner. The evidence also supports a multifactorial background for BMI and suggests that the frequencies of these two factors, one of which appears to be a gene, may vary among diverse populations in the United States.
Preadipocyte Screening by Laminin in Porcine Stromal Vascular Cell Cultures
Authors: Yu Z.K. , Hausman G.J.
Published: September 2012

Objective: To determine if subpopulations of cells in stromal vascular (S‐V) cultures could be segregated and separated based on affinity for laminin substratum.

Research Methods and Procedures: S‐V cells were seeded and allowed to attach for various times; 4 hours was found to be optimal for cell attachment. Cultures were rinsed after 4 hours of seeding, and S‐V cells were divided into three subpopulations based on affinity for laminin: (1) cells that did not attach to laminin; (2) cells that had a low affinity for laminin; and (3) cells that had a high affinity for laminin. After 24 hours, cultures were either stained for the AD‐3 antigen (a marker for preadipocytes), C/EBP‐α (a terminal differentiation marker), or C/EBP‐8 (an early preadipocyte marker). Companion cultures were treated with various media for 9 days and stained with oil red‐O.

Results: Cells with a high affinity for laminin had the highest proportion of AD‐3 and C/EBP‐α positive cells and the highest proportion of fat cells after treatment with insulin ± dexamethasone. Cells with a low affinity for laminin had the1 highest proportion of C/EBP‐8 cells and the highest proportion of fat cells after treatment with fetal bovine serum+dexamethasone, followed by insulin.

Discussion: These results indicate that differentiating preadipocytes adhere to laminin to a much greater degree than do non‐preadipocytes. Therefore, laminin‐coated dishes can be used to screen S‐V cells to produce preadipocyte or fibroblast‐enriched S‐V cultures.
Serum Leptin Concentration and Insulin Sensitivity in Men with Abdominal Obesity
Authors: Johannsson Gudmundur , Karlsson Cecilia , Lönn Lars , Mårin Per , Björntorp Per , Sjöström Lars , Carlsson Björn , Carlsson Lena M.S. , Bengtsson Bengt‐Åke
Published: September 2012

JOHANNSSON, GUDMUNDUR, CECILIA KARLSSON, LARS LÖNN, PER MÅRIN, PER BJÖRNTORP, LARS SJÖSTRÖM, BJÖRN CARLSSON, LENA M.S. CARLSSON, BENGT‐ÅKE BENGTSSON. Serum leptin concentration and insulin sensitivity in men with abdominal obesity. Obes Res. 1998;6:416–421.

Objective: We have examined the association between generalized adiposity, abdominal adiposity, insulin sensitivity, and serum levels of leptin in a cross‐sectional study of abdominally obese men.

Research Methods and Procedures: Thirty men, 48 to 66 years of age with a body mass index (BMI) of between 25 kg/m2 and 35 kg/m2 and a waist hip ratio of <0.95, were included in the study. Serum leptin concentration was measured using radioimmunoassay. Total body fat percentage was determined from total body potassium, abdominal adiposity was measured by computed tomography, and the glucose disposal rate (GDR) was measured during an euglycemic, hyperinsulinemic glucose clamp.

Results: Significant correlations were found between serum leptin concentration and BMI, percentage body fat, abdominal subcutaneous adipose tissue, serum insulin, GDR, and 24‐hour urinary‐free Cortisol. In a multiple regression analysis, it was shown that abdominal subcutaneous adipose tissue, GDR, and BMI explained 72% of the variability of serum leptin concentration. GDR demonstrated an independent inverse correlation with serum leptin concentration.

Discussion: In abdominally obese men with insulin resistance, it was demonstrated that most of the individual variability in serum leptin concentration was explained by the amount of subcutaneous abdominal adipose tissue, insulin sensitivity, and BMI.
Serum Leptin and Weight Gain Over 8 Years in African American and Caucasian Young Adults
Authors: Folsom Aaron R. , Jensen Michael D. , Jacobs David R. , Hilner Joan E. , Tsai Albert W. , Schreiner Pamela J.
Published: September 2012

FOLSOM, AARON R., MICHAEL D. JENSEN, DAVID R. JACOBS, JR., JOAN E. HILNER, ALBERT W. TSAI, AND PAMELA J. SCHREINER. Serum leptin and weight gain over 8 years in African American and Caucasian young adults. Obes Res. 1999;7:1–8.

Objective: There is considerable interest in how to prevent weight gain in adulthood. Leptin, a peptide hormone expressed in adipose tissue, is believed to signal the central nervous system about the level of body fat stores, and thereby may control appetite. Little information exists on whether the serum leptin concentration influences long‐term weight changes in the free‐living population.

Research Methods and Procedures: From an ongoing cohort study of young African American and white adults, we selected a sample of participants (n=492), stratified on sex, race, and weight changes over 8 years. Serum leptin was measured on stored specimens using a radioimmunoassay. Weight change was modeled in relation to baseline leptin concentrations.

Results: Cross‐sectionally, leptin concentration was associated positively with body mass index, negatively with physical activity level, and was higher in women than men. These variables explained 72% of the variance in serum leptin. Over the 8 years, the sample gained an average of 7.8 kg (standard deviation = 10.8). There was no evidence that 8‐year weight change was associated with initial leptin concentration: 8‐year weight change was only 0.5 kg less (95% confidence interval = −1.8 to 0.8, p = 0.47) per each 10 ng/ mL increment (approximately one standard deviation) of baseline leptin. In contrast, leptin change correlated highly (r = 0.62) with weight change.

Discussion: Our data corroborate evidence that adiposity determines leptin levels but do not support the hypothesis that leptin deficiency plays an important role in obesity in the general population.
Energy Expenditure Determined by Self‐Reported Physical Activity Is Related to Body Fatness
Authors: Buchowski Maciej S. , Townsend Karen M. , Chen Kong Y. , Acra Sari A. , Sun Ming
Published: September 2012

BUCHOWSKI, MACIEJ S., KAREN M. TOWNSEND, KONG Y. CHEN, SARI A. ACRA, AND MING SUN. Energy expenditure determined by self‐reported physical activity is related to body fatness. Obes. Res. 1999;7:23–33.

Objective: Activity self‐reports are a commonly used tool in assessing daily physical activity (PA) and associated energy expenditure (EE). This study examined the effect of relative body fatness (%BF) on differences between self‐reported and measured duration and associated EE in healthy adults. Research Methods and Procedures: Men and women (n= 115, age 38±9 years), ranging in %BF from 7.9% to 58.9%, spent two separate days (normal and exercise) in a whole‐room indirect calorimeter where EE was measured. While in the room calorimeter, subjects reported the type, intensity, and duration of each performed PA. The Compendium of Physical Activity was used to calculate the energy cost of each reported activity. The EE of all self‐reported activities (EEr) was categorized into four intensity levels, synchronized, and compared with EE from the room calorimeter (EEm).

Results: With increasing %BF, subjects significantly overestimated duration of more strenuous activities (≥4.5), while underestimating moderate activities (2.5 to 4.4 metabolic equivalents (METs)). Misreporting of duration and/or intensity caused an overestimation or underestimation of PA‐associated EE at these levels. Reported EE sleep was lower than measured EE sleep, although both had similar durations. As a result, total EEr was similar to EEm.

Discussion: Individual variability of daily total PA and associated EE generated from self‐reports in adults is high. Persons with a higher %BF report duration and/or intensity of moderate to high levels of PA with lower accuracy than leaner individuals. We conclude using the Compendium of Physical Activity is not suitable for the accurate estimation of self‐reported EE of AA in adults with a higher %BF.
Predictors of Weight Maintenance
Authors: Pasman Wilrike J. , Saris Wim H.M. , Westerterp‐Plantenga Margriet S.
Published: September 2012

PASMAN, WILRIKE J., WIM H.M. SARIS, AND MARGRIET S. WESTERTERP‐PLANTENGA. Predictors of weight maintenance. Obes Res. 1999;7:43–50.

Objective: To obtain predictors of weight maintenance after a weight‐loss intervention.

Research Methods and Procedures: An overall analysis of data from two‐long intervention studies [n = 67 women; age: 37.9±1.0 years; body weight (BW): 87.0±1.2 kg; body mass index: 32.1±0.5 kg‐m−2; % body fat: 42.4±0.5%]. Subjects were measured before a very low energy diet (month 0), after the very low energy diet of 2 months (month 2) and after a 14‐month follow‐up phase (at 16 months), in which fiber or a carbohydrate‐containing food supplement was supplied. The baseline measurements and the changes in parameters induced by the diet intervention were used to predict the changes in BW in the follow‐up phase [ΔBW(2–16)].

Results: Multiple regression analysis revealed that 50% (p<0.71) of the variability in weight regain could be explained by pphysiological and behavioral factors. These were: frequency of previous dieting (r2 = 0.27, p<0.05), hunger score (measured with the three‐factor eating behavior questionnaire), and change in 24‐hour resting metabolic rate (RMR). Frequent dieters showed significantly more weight regain than less frequent dieters (8.8±1.0 kg vs. 5.1 ±0.8 kg, p<0.01). Subjects having parents with obesity regained almost significantly more weight than subjects with lean parents (8.5±0.2 kg vs. 5.1±1.5 kg, respectively; p = 0.06).

Discussion: Physiological (ΔRMR‐24 hours) and behavioral factors (previous frequency of dieting and hunger score) predicted failure of weight maintenance and, as such, can be used to identify women who are at risk for weight regain.
Endocrine Regulation of Fetal Adipose Tissue Metabolism in the Pig: Interaction of Porcine Growth Hormone and Thyroxine
Authors: Hausman D.B. , Hausman G.J. , Martin R.J.
Published: September 2012

HAUSMAN, D.B., G.J. HAUSMAN, AND R.J. MARTIN. Endocrine regulation of fetal adipose tissue metabolism in the pig: interaction of porcine growth hormone and thyroxine. Obes Res. 1999;7:76–82.

Objective: This study tested the hypothesis that combined treatment of thyroxine (T4) and growth hormone (GH) could normalize cellular and metabolic aspects of adipose tissue development of hypophysectomized fetal pigs.

Research Methods and Procedures: On day 70 of gestation, pig fetuses were hypophysectomized by microcauterization or remained intact. Hypophysectomized fetuses remained untreated or were treated from day 90 to day 105 of gestation with T4, GH, or a combination of both hormones.

Results: Body weights were unaffected by hypophysectomy or hormone treatment. De novo lipogenesis in subcutaneous adipose tissue was increased 10‐fold by hypophysectomy, consistent with our previous results. This increase was abolished by GH treatment in the hypophysectomized fetuses. In contrast, T4 treatment of the hypophysectomized fetuses resulted in a 12‐fold further increase in adipose tissue lipogenesis, an effect that was negated by concomitant administration of GH. Lipolytic response to isoproterenol was decreased by hypophysectomy, unaffected by GH treatment, and restored to intact values by T4 or by T4+GH treatment in the hypophysectomized fetuses.

Discussion: In contrast to T4, GH does not influence serum insulin‐like growth factor‐I or adipose tissue lipolysis, but decreases lipogenesis in the fetal pig. However, replacing both T4 and GH normalized hypophysectomized fetuses to a greater extent than either GH or T4 alone. Thus, any influence of thyroid hormones on stimulating adipose tissue lipogenesis in the developing fetal pig may be normally counterregulated by pituitary‐derived growth hormone.
Double‐Blind, Randomized, Placebo‐Controlled Clinical Trials with Non‐Prescription Medications for the Treatment of Obesity
Authors: Greenway Frank , Heber David , Raum William , Morales Silvia
Published: September 2012

GREENWAY, FRANK, DAVID HEBER, WILLIAM RAUM, AND SILVIA MORALES. Double‐blind, randomized, placebo‐controlled clinical trials with non‐prescription medications for the treatment of obesity. Obes Res.

Objective: Phenylpropanolamine (PPA) and benzocaine are non‐prescription medications approved for treating obesity. The dose of PPA for weight loss is 75 mg/day. PPA has the same chemical similarity to pseudoephedrine that amphetamine has to methamphetamine. Because benzocaine causes weight loss by altering taste and PPA by central appetite suppression, they may induce additional weight loss when combined. These studies explore the safety and efficacy of low‐dose PPA, pseudoephedrine, and PPA with benzocaine in causing weight loss.

Research Methods and Procedures: Study 1 compared PPA 12. 5 mg tid with 25 mg tid and placebo in a 6‐week trial in 108 obese subjects. Study 2 compared pseudoephedrine 120 mg/day and a placebo in a 12‐week trial with 72 obese subjects. Study 3 compared 4 groups of 20 obese subjects using PPA 75 mg/day, benzocaine gum 96 mg/day, PPA with benzocaine gum, and a placebo over 12 weeks.

Results: Both doses of PPA gave twice the weight loss of placebo, but the difference did not reach statistical significance. Pseudoephedrine was no different than placebo in inducing weight loss. The PPA with benzocaine group had more adverse events than the benzocaine group (p = 0. 03), the placebo group (p = 0. 03), or the PPA group (p = 0. 09) without additional weight loss.

Discussion: We conclude that further studies with low‐dose PPA for weight loss are indicated, that pseudoephedrine is not effective for weight loss, and that adding benzocaine to phenylpropanolamine increases adverse effects without increasing weight loss.
Racial Differences in Metabolic Predictors of Obesity among Postmenopausal Women
Authors: Nicklas Barbara J. , Berman Dora M. , Davis Dawn C. , Dobrovolny C. Lynne , Dennis Karen E.
Published: September 2012

NICKLAS, BARBARA S., DORA M. BERMAN, DAWN C. DAVIS, C. LYNNE DOBROVOLNY, AND KAREN E. DENNIS. Racial differences in metabolic predictors of obesity among postmenopausal women. Ober Res.

Objective: This study determined whether there are racial differences in resting metabolic rate (RMR), fat oxidation, and maximal oxygen consumption (VO,max) in obese [body mass index (BMI = 34±2 kg/m2)], postmenopausal (58±2 years) women.

Research Methods and Procedures: Twenty black and 20 white women were matched for fat mass and lean mass (LM), as determined by dual energy X‐ray absorptiometry. RMR and fat oxidation were measured by indirect calorimetry in the early morning after a 12‐hour fast using the ventilated hood technique. VO2max was measured on a treadmill during a progressive exercise test to voluntary exhaustion.

Results: RMR, adjusted for differences in LM, was 5% higher in white than black women (1566±27 and 1490±26 kcal/day, respectively; p<0. 05); and fat oxidation rate was 17% higher in white than black women (87±4 and 72±3 g/day, respectively; p<0. 01). VO2max (L/minute) was 150 mL per minute (8%) higher (p<0. 05) in white than black women. VO2max correlated with LM in black (r = 0. 44, p = 0. 05) and white (r=0. 53, p<0. 05) women, but the intercept of the regression line was higher in white than black women (p<0. 05), with no significant difference in slopes. In a multiple regression model including race, body weight, LM, and age, LM was the only independent predictor of RMR (r2 = 0. 46, p<0. 0001), whereas race was the only independent predictor of fat oxidation (r2 = 0. 18,p<0. 05). The best predictors of VO,max were LM (r2 = 0. 22, p<0. 05) and race (cumulative r2 = 0. 30, p<0. 05).

Discussion: These results show there are racial differences in metabolic predictors of obesity. Determination of whether these ethnic differences lead to, or are an effect of, obesity status or other lifestyle factors requires further study.
Serum Leptin in Elderly People: Associations with Sex Hormones, Insulin, and Adipose Tissue Volumes
Authors: Baumgartner Richard N. , Ross Robert R. , Waters Debra L. , Brooks William M. , Morley John E. , Montoya George D. , Garry Philip J.
Published: September 2012

BAUMGARTNER, RICHARD N., ROBERT R. ROSS, DEBRA L. WATERS, WILLIAM M. BROOKS, JOHN E. MORLEY, GEORGE D. MONTOYA, AND PHILIP J. GARRY. Serum leptin in elderly people: associations with sex hormones, insulin, and adipose tissue volumes. Obes Res.

Objective There are few data for associations of serum leptin with body fat, fat distribution, sex hormones, or fasting insulin in elderly adults. We hypothesized that the sex difference in serum leptin concentrations would disappear after adjustment for subcutaneous, but not visceral body fat. Serum leptin would not be associated with sex hormone concentrations or serum fasting insulin after adjusting for body fat and fat distribution.

Research Methods and Procedures Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) volumes were measured using magnetic resonance imaging in a cross‐sectional sample of 56 nondiabetic, elderly men and women aged 64 years to 94 years. Serum leptin, sex hormones (testosterone and estrone), sex hormone‐binding globulin, and fasting insulin were also measured. Nine women were taking hormone replacement, and five men were clinically hypogonadal.

Results Leptin was significantly associated with both SAT and VAT in each sex. Adjustment for SAT reduced the sex difference in leptin by 56%, but adjustment for VAT increased the difference by 25%. Leptin was not associated with serum estrone or hormone replacement therapy in the women, but had a significant, negative association with testosterone in the men that was independent of SAT, but not VAT. Leptin was significantly associated with fasting insulin in both sexes independent of age, sex hormones, sex hormone‐binding globulin, VAT and SAT.

Discussion Sex difference in serum leptin is partly explained by different amounts of SAT. Studies including both men and women should adjust for SAT rather than total body fat that includes VAT. The sex difference in serum leptin is not due to estrogen, but may be partly explained by testosterone. Testosterone is negatively associated with leptin in men, but the association is confounded with VAT. Leptin is associated with fasting insulin in non‐diabetic elderly men and women independent of body fat, fat distribution. or sex hormones.
Effects of Targeting Higher Vancomycin Trough Levels on Clinical Outcomes and Costs in a Matched Patient Cohort
Authors: Kullar Ravina , Davis Susan L. , Taylor Thomas N. , Kaye Keith S. , Rybak Michael J.
Published: September 2012

Study Objective

To compare clinical outcomes and costs in patients treated with the new vancomycin guidelines recommending goal serum trough concentrations of 15–20 mg/L versus patients treated with vancomycin doses targeting trough concentrations 5–20 mg/L prior to the new guidelines.

Design

Retrospective quasi‐experimental study.

Setting

Urban level I trauma center.

Patients

A total of 200 patients treated with vancomycin for at least 72 hours for confirmed, complicated methicillin‐resistant Staphylococcus aureus (MRSA) bacteremia during one of two study phases relative to the implementation of the vancomycin dosing guidelines targeting serum trough concentrations of 15–20 mg/L: 2005–2007 (preperiod phase) and 2008–2010 (postperiod phase). One hundred patients in each phase were matched in a 1:1 ratio according to diagnosis, any concomitant nephrotoxic agents (e.g., aminoglycosides, colistin, acyclovir), and age ± 5 years.

Measurements and Main Results

Patients in the preperiod had significantly lower success rates with vancomycin than those in the postperiod (45% vs 60%, p=0.034). Median length of stay (LOS) was not significantly higher in patients in the preperiod versus postperiod (15 days vs 13.5 days; p=0.28), and patients in the preperiod received a longer median duration of vancomycin versus those in the postperiod (13 days vs 8.5 days; p<0.001). No statistically significant difference was noted in total hospital costs for patients treated with vancomycin during the preperiod versus the postperiod ($32,754 vs $27,709, p=0.147). However, total drug and monitoring costs of vancomycin were significantly higher for patients in the postperiod. Initial vancomycin trough levels were significantly lower in patients in the preperiod versus postperiod (12.3 mg/L vs 15.8 mg/L, p=0.02). Patients in the preperiod had lower rates of nephrotoxicity than those in the postperiod, although this difference was not statistically significant (15% vs 18%; p=0.85). Median (interquartile range) LOS was significantly longer in patients who developed nephrotoxicity compared with patients who did not develop nephrotoxicity (17 days [11.5–36.5 days] vs 14 days [9–24 days], p=0.017). Costs associated with measurement of serum creatinine concentrations and vancomycin trough levels as well as labor were significantly higher in patients who developed nephrotoxicity.

Conclusion

Higher vancomycin trough concentrations improved outcomes in patients with complicated MRSA bacteremia. In addition, more aggressive dosing was shown to significantly decrease overall duration of vancomycin therapy, which may affect total hospital LOS and cost. Patients who experienced nephrotoxicity had a significantly longer hospital LOS. Additional studies evaluating optimal therapy for MRSA bacteremia in a larger cohort of matched patients are warranted.
Probable Interaction Between Lycium barbarum (Goji) and Warfarin
Authors: Rivera Claudio A. , Ferro Carol L. , Bursua Adam J. , Gerber Ben S.
Published: September 2012

Lycium barbarum (also called goji berry), a Chinese herb used as a supplement for health benefits, is traditionally consumed by the Chinese in the form of a tea. Goji juice, a widely available beverage in the United States, also contains this herb. We describe a 71‐year‐old Ecuadorean‐American woman who was taking warfarin and was hospitalized for a markedly elevated, indeterminate international normalized ratio (INR) (prothrombin time > 120 sec) after consumption of goji juice. She had undergone knee surgery approximately 3 months earlier at which time warfarin therapy was started. She reported no changes in dietary habits or lifestyle other than drinking goji juice for 4 days before hospitalization. On presentation to the emergency department, she described symptoms of epistaxis, bruising, and rectal bleeding. After discontinuation of the goji juice and warfarin, the patient was treated with phytonadione, and her INR decreased to 2.6 over 2 days. Application of the Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 6) between the patient's elevated INR with associated bleeding and her concomitant use of L. barbarum and warfarin. Two other published reports have described similar interactions between warfarin and a tea containing L. barbarum. Patients should be educated about avoiding popular herbal drinks, such as goji juice, that contain L. barbarum while they are taking warfarin. In addition, clinicians should question patients about their use of herbal therapies and document such use in their medical records before prescribing drugs such as warfarin.
Retracted Publications in the Drug Literature
Authors: Samp Jennifer C. , Schumock Glen T. , Pickard A. Simon
Published: September 2012

Recent studies have suggested an increase in the number of retracted scientific publications. It is unclear how broadly the issue of misleading and fraudulent publications pertains to retractions of drug therapy studies. Therefore, we sought to determine the trends and factors associated with retracted publications in drug therapy literature. A PubMed search was conducted to identify retracted drug therapy articles published from 2000–2011. Articles were grouped according to reason for retraction, which was classified as scientific misconduct or error. Scientific misconduct was further divided into data fabrication, data falsification, questions of data veracity, unethical author conduct, and plagiarism. Error was defined as duplicate publication, scientific mistake, journal error, or unstated reasons. Additional data were extracted from the retracted articles, including type of article, funding source, author information, therapeutic area, and retraction issue. A total of 742 retractions were identified from 2000–2011 in the general biomedical literature, and 102 drug studies met our inclusion criteria. Of these, 73 articles (72%) were retracted for a reason classified as scientific misconduct, whereas 29 articles (28%) were retracted for error. Among the 73 articles classified as scientific misconduct, those classified as unethical author conduct (32 articles [44%]) and data fabrication (24 articles [33%]) constituted the majority. The median time from publication of the original article to retraction was 31 months (range 1–130). Fifty percent of retracted articles did not state a funding source, whereas pharmaceutical manufacturer funding accounted for only 13 articles (13%) analyzed. Many retractions were due to repeat offenses by a small number of authors, with nearly 40% of the retracted studies associated with two individuals. We found that a greater proportion of drug therapy articles were retracted for reasons of misconduct and fraud compared with other biomedical studies. It is important for health care practitioners to monitor the literature for retractions so that recommendations for drug therapy and patient management may be modified accordingly.