bluuebunny/crossref_metadata_2025 huggingface dataset:
Water temperature, not fish morph, determines parasite infections of sympatric Icelandic threespine sticklebacks (Gasterosteus aculeatus)
Authors: Karvonen Anssi , Kristjánsson Bjarni K. , Skúlason Skúli , Lanki Maiju , Rellstab Christian , Jokela Jukka
Published: April 2013

Parasite communities of fishes are known to respond directly to the abiotic environment of the host, for example, to water quality and water temperature. Biotic factors are also important as they affect the exposure profile through heterogeneities in parasite distribution in the environment. Parasites in a particular environment may pose a strong selection on fish. For example, ecological differences in selection by parasites have been hypothesized to facilitate evolutionary differentiation of freshwater fish morphs specializing on different food types. However, as parasites may also respond directly to abiotic environment the parasite risk does not depend only on biotic features of the host environment. It is possible that different morphs experience specific selection gradients by parasites but it is not clear how consistent the selection is when abiotic factors change. We examined parasite pressure in sympatric morphs of threespine stickleback (Gasterosteus aculeatus) across a temperature gradient in two large Icelandic lakes, Myvatn and Thingvallavatn. Habitat‐specific temperature gradients in these lakes are opposite. Myvatn lava rock morph lives in a warm environment, while the mud morph lives in the cold. In Thingvallavatn, the lava rock morph lives in a cold environment and the mud morph in a warm habitat. We found more parasites in fish living in higher temperature in both lakes, independent of the fish morph, and this pattern was similar for the two dominating parasite taxa, trematodes and cestodes. However, at the same time, we also found higher parasite abundance in a third morph living in deep cold–water habitat in Thingvallavatn compared to the cold‐water lava morph, indicating strong effect of habitat‐specific biotic factors. Our results suggest complex interactions between water temperature and biotic factors in determining the parasite community structure, a pattern that may have implications for differentiation of stickleback morphs.
New Dynamic Self‐Consistent Mathematical Model and Torque Characteristics of Permanent‐Magnet Synchronous Motors with Magnetic Cross‐Coupling
Authors: Shinnaka Shinji
Published: April 2013

This paper proposes a new dynamic mathematical model of permanent‐magnet synchronous motors (PMSMs) with magnetic cross‐coupling and presents a new analysis of the torque characteristics of the motors. Generally speaking, dynamic mathematical models used for the design and analysis of PMSM control systems must consist of three basic equations that describe the main motor characteristics as an electrical circuit, torque generator, and electromechanical energy converter. In order to obtain reasonably compact models, some characteristics have to be approximated. However, in the case where the approximations used in the three basic equations are different from each other, the dynamic mathematical model often loses self‐consistency and becomes self‐contradictory. The proposed model, which takes the magnetic cross‐coupling into account, is self‐consistent and compact, and its effectiveness is validated by experimental data. Using the self‐consistency and compactness, this study presents a new analysis of the torque characteristics of PMSMs, focusing on efficient torque generation. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(1): 42–55, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22382
Benzoylthiourea–Pyrrolidine as Another Bifunctional Organocatalyst: Highly Enantioselective Michael Addition of Cyclohexanone to Nitroolefins
Authors: Ban Shu‐rong , Zhu Xi‐xia , Zhang Zhi‐ping , Xie Hong‐yu , Li Qing‐shan
Published: April 2013

Asymmetric Michael addition of cyclohexanone to nitrostyrenes in the presence of organocatalyst 1 (10 mol‐%) and 2,4‐dichlorobenzoic acid (10 mol‐%) afforded the corresponding synthetically valuable γ‐nitroketones in moderate to good yields with high diastereoselectivities (up to >99:1 dr) and high enantioselectivities (up to >99 % ee) under mild conditions.
SRSF1 and SRSF9 RNA binding proteins promote Wnt signalling‐mediated tumorigenesis by enhancing β‐catenin biosynthesis
Authors: Fu Yu , Huang Binlu , Shi Zhen , Han Jiayu , Wang Ying , Huangfu Jieqiong , Wu Wei
Published: April 2013

Wnt/β‐catenin signalling is widely implicated in embryogenesis, tissue homeostasis and tumorigenesis. The key event in Wnt signalling activation is β‐catenin accumulation, which is controlled by both its production and degradation. However, much more emphasis has been placed on the understanding of its degradation. Here, we show that the synthesis of β‐catenin protein, which requires a group of serine/arginine‐rich splicing factors (SRSF), also contributes to its tumorigenic activity. Overexpression of SRSF1 and SRSF9 promote β‐catenin accumulation via the recruitment of β‐catenin mRNA and by enhancing its translation in an mTOR‐dependent manner. We further demonstrate that, like SRSF1, SRSF9 is also an oncogene, and is frequently overexpressed in multiple types of human tumours. Finally, our results suggest that promoting degradation and blocking production of β‐catenin synergistically reduce β‐catenin levels under pathological conditions and that a combinational therapy could be a promising approach for the treatment of cancer patients.
Resolution of inflammation: an integrated view
Authors: Ortega‐Gómez Almudena , Perretti Mauro , Soehnlein Oliver
Published: April 2013

Resolution of inflammation is a coordinated and active process aimed at restoration of tissue integrity and function. This review integrates the key molecular and cellular mechanisms of resolution. We describe how abrogation of chemokine signalling blocks continued neutrophil tissue infiltration and how apoptotic neutrophils attract monocytes and macrophages to induce their clearance. Uptake of apoptotic neutrophils by macrophages reprograms macrophages towards a resolving phenotype, a key event to restore tissue homeostasis. Finally, we highlight the therapeutic potential that derives from understanding the mechanisms of resolution.
Mechanism of tropical low‐cloud response to surface warming using weather and climate simulations
Authors: Demoto Satoru , Watanabe Masahiro , Kamae Youichi
Published: April 2013

To understand mechanisms of shortwave cloud‐radiative feedback to global warming in a general circulation model (GCM), we analyzed the response of tropical clouds to uniform increase of sea surface temperature in an atmospheric GCM with two different experimental designs: a single Atmospheric Model Intercomparison Project (AMIP) run for 30 years and a series of 10 day weather hindcasts following the Transpose AMIP II (TAMIP). Given the fast time scale of cloud processes, the hindcast ensemble can capture initial transient responses toward equilibrium obtained in the AMIP experiment, which shows a reduction of low clouds over tropical subsidence regions. The reduction of clouds occurs in the first 10 days in TAMIP when the marine boundary layer (MBL) is destabilized because of contrast between fast and slow warming in the MBL and aloft. Enhanced evaporation from the sea surface that should moisten the MBL through turbulent mixing is suppressed by a reduced surface wind speed associated with a slowdown of the Walker circulation. The sign of the low‐cloud change over the subsidence regime is thus determined roughly by competition between convective drying and turbulent moistening of the MBL.
Quantifying the modern recharge of the “fossil” Sahara aquifers
Authors: Gonçalvès J. , Petersen J. , Deschamps P. , Hamelin B. , Baba‐Sy O.
Published: April 2013

The North‐Western Sahara Aquifer System (NWSAS), one of the world's largest groundwater systems, shows an overall piezometric decline associated with increasing withdrawals. Estimating the recharge rate in such a semiarid system is challenging but crucial for sustainable water development. In this paper, the recharge of the NWSAS is estimated using a regional water budget based on GRACE terrestrial water storage monthly records, soil moisture from the GLDAS (a land data system that assimilates hydrological information), and groundwater pumping rates. A cumulated natural recharge rate of 1.40 ± 0.90 km3 yr−1is estimated for the two main aquifers. Our results suggest a renewal rate of about 40% which partly contradicts the premise that recharge in this area should be very low or even null. Aquifer depletion inferred from our analysis is consistent with observed piezometric head decline in the two main aquifers in the region. Annual recharge variations were also estimated and vary between 0 and 4.40 km3 yr−1for the period 2003–2010. These values correspond to a recharge between 0 and 6.75 mm yr−1 on the 650,000 km2of outcropping areas of the aquifers, which is consistent with the expected weak and sporadic recharge in this semiarid environment. These variations are also in line with annual rainfall variation with a lag time of about 1 year.
Scaling of fluid flow versus fracture stiffness
Authors: Petrovitch Christopher L. , Nolte David D. , Pyrak‐Nolte Laura J.
Published: April 2013

Seismic characterization of fluid flow through fractures requires a fundamental understanding of the relationship between the hydraulic and mechanical properties of fractures. A finite‐size scaling analysis was performed on fractures with weakly correlated random aperture distributions to determine the fundamental scaling relationship between fracture stiffness and fracture fluid flow. From computer simulations, the dynamic transport exponent, which provides the power law dependence, was extracted and used to collapse the flow‐stiffness relationships from multiple scales into a single scaling function. Fracture specific stiffness was determined to be a surrogate for void area that is traditionally used in percolation studies. The flow‐stiffness scaling function displays two exponentially dependent regions above and below the transition into the critical regime. The transition is governed by the stressed flow paths when the flow path geometry deforms from a sheet‐like topology to a string‐like topology. The resulting hydromechanical scaling function provides a link between fluid flow and the seismic response of a fracture.
Putting the capital ‘A’ in CoCoRAHS: an experimental programme to measure albedo using the Community Collaborative Rain, Hail & Snow (CoCoRaHS) Network
Authors: Burakowski Elizabeth , Wake Cameron P. , Dibb Jack E. , Stampone Mary
Published: April 2013

The Community Collaborative Rain, Hail & Snow (CoCoRaHS) Network is a community‐based network of weather observers and the largest provider of daily precipitation observations in the USA. In this study, we embrace the CoCoRaHS mission to use low‐cost measurement tools, provide training and education, and utilize an interactive website to create the first volunteer snow albedo network to collect high‐quality albedo data for research and education applications. We trained a sub‐set of 18 CoCoRaHS observers in the state of New Hampshire to collect albedo, snow depth, and snow density between 23 November 2011 and 15 March 2012. At less than $700 per observer, CoCoRAHS data measured using an Apogee MP‐200 pyranometer fall within ±0.05 of albedo values collected from a Kipp and Zonen CMA6 at local solar noon. CoCoRAHS values range from 0.99 for fresh snow to 0.34 for shallow, aged snow. Snow‐free albedo ranges from 0.09 to 0.39, depending on the underlying ground cover. In the 2011/2012 dataset, albedo increases logarithmically with snow depth and decreases linearly with snow density. The latter relationship is inferred to be a proxy for increasing snow grain size as snowpack ages and compacts, supported by spectral albedo measurements collected with an Analytical Spectral Devices FieldSpec 4 spectrometer. Copyright © 2013 John Wiley & Sons, Ltd.
Automated synthesis and purification of [18F]fluoro‐[di‐deutero]methyl tosylate
Authors: Beyerlein Friederike , Piel Markus , Höhnemann Sabine , Rösch Frank
Published: April 2013

Automated synthetic procedures of [18F]fluoro‐[di‐deutero]methyl tosylate on a GE TRACERlab FX F‐N module and a non‐commercial synthesis module have been developed. The syntheses included azeotropic drying of the [18F]fluoride, nucleophilic 18F‐fluorination of bis(tosyloxy)‐[di‐deutero]methane, HPLC purification and subsequent formulation of the synthesized [18F]fluoro‐[di‐deutero]methyl tosylate (d2‐[18F]FMT) in organic solvents. Automation shortened the total synthesis time to 50 min, resulting in an average radiochemical yield of about 50% and high radiochemical purity (>98%). The possible application of this procedure to commercially available synthesis modules might be of significance for the production of deuterated 18F‐fluoromethylated imaging probes in the future. Copyright © 2013 John Wiley & Sons, Ltd.
Canine body composition quantification using 3 tesla fat–water MRI
Authors: Gifford Aliya , Kullberg Joel , Berglund Johan , Malmberg Filip , Coate Katie C. , Williams Phillip E. , Cherrington Alan D. , Avison Malcolm J. , Welch E. Brian
Published: April 2013

Purpose

To test the hypothesis that a whole‐body fat–water MRI (FWMRI) protocol acquired at 3 Tesla combined with semi‐automated image analysis techniques enables precise volume and mass quantification of adipose, lean, and bone tissue depots that agree with static scale mass and scale mass changes in the context of a longitudinal study of large‐breed dogs placed on an obesogenic high‐fat, high‐fructose diet.

Materials and Methods

Six healthy adult male dogs were scanned twice, at weeks 0 (baseline) and 4, of the dietary regiment. FWMRI‐derived volumes of adipose tissue (total, visceral, and subcutaneous), lean tissue, and cortical bone were quantified using a semi‐automated approach. Volumes were converted to masses using published tissue densities.

Results

FWMRI‐derived total mass corresponds with scale mass with a concordance correlation coefficient of 0.931 (95% confidence interval = [0.813, 0.975]), and slope and intercept values of 1.12 and −2.23 kg, respectively. Visceral, subcutaneous and total adipose tissue masses increased significantly from weeks 0 to 4, while neither cortical bone nor lean tissue masses changed significantly. This is evidenced by a mean percent change of 70.2% for visceral, 67.0% for subcutaneous, and 67.1% for total adipose tissue.

Conclusion

FWMRI can precisely quantify and map body composition with respect to adipose, lean, and bone tissue depots. The described approach provides a valuable tool to examine the role of distinct tissue depots in an established animal model of human metabolic disease. J. Magn. Reson. Imaging 2014;39:485–491. © 2013 Wiley Periodicals, Inc.
Mortality and major morbidity after tonsillectomy
Authors: Goldman Julie L. , Baugh Reginald F. , Davies Louise , Skinner Margaret L. , Stachler Robert J. , Brereton Jean , Eisenberg Lee D. , Roberson David W. , Brenner Michael J.
Published: April 2013

Objective/Hypothesis

To report data on death or permanent disability after tonsillectomy.

Study Design

Electronic mail survey.

Methods

A 32‐question survey was disseminated via the American Academy of Otolaryngology–Head and Neck Surgery electronic newsletter. Recipients were queried regarding adverse events after tonsillectomy, capturing demographic data, risk factors, and detailed descriptions. Events were classified using a hierarchical taxonomy.

Results

A group of 552 respondents reported 51 instances of post‐tonsillectomy mortality, and four instances of anoxic brain injury. These events occurred in 38 children (71%), 15 adults (25%), and two patients of unstated age (4%). The events were classified as related to medication (22%), pulmonary/cardiorespiratory factors (20%), hemorrhage (16%), perioperative events (7%), progression of underlying disease (5%), or unexplained (31%). Of unexplained events, all but one occurred outside the hospital. One or more comorbidities were identified in 58% of patients, most often neurologic impairment (24%), obesity (18%), or cardiopulmonary compromise (15%). A preoperative diagnosis of obstructive sleep apnea was not associated with increased risk of death or anoxic brain injury. Most events (55%) occurred within the first 2 postoperative days. Otolaryngologists who reported performing <200 tonsillectomies per year were more likely to report an event (P < .001).

Conclusions

This study, the largest collection of original reports of post‐tonsillectomy mortality to date, found that events unrelated to bleeding accounted for a preponderance of deaths and anoxic brain injury. Further research is needed to establish best practices for patient admission, monitoring, and pain management. Laryngoscope, 123:2544–2553, 2013

Level of Evidence

N/A.
Quantitative mouse renal perfusion using arterial spin labeling
Authors: Rajendran Reshmi , Lew Si Kang , Yong Cai Xian , Tan Jolena , Wang Danny J. J. , Chuang Kai‐Hsiang
Published: April 2013

Information on renal perfusion is essential for the diagnosis and prognosis of kidney function. Quantification using gadolinium chelates is limited as a result of filtration through renal glomeruli and safety concerns in patients with kidney dysfunction. Arterial spin labeling MRI is a noninvasive technique for perfusion quantification that has been applied to humans and animals. However, because of the low sensitivity and vulnerability to motion and susceptibility artifacts, its application to mice has been challenging. In this article, mouse renal perfusion was studied using flow‐sensitive alternating inversion recovery at 7 T. Good perfusion image quality was obtained with spin‐echo echo‐planar imaging after controlling for respiratory, susceptibility and fat artifacts by triggering, high‐order shimming and water excitation, respectively. High perfusion was obtained in the renal cortex relative to the medulla, and signal was absent in scans carried out post mortem. Cortical perfusion increased from 397 ± 36 (mean ± standard deviation) to 476 ± 73 mL/100 g/min after switching from 100% oxygen to carbogen with 95% oxygen and 5% carbon dioxide. The perfusion in the medulla was 2.5 times lower than that in the cortex and changed from 166 ± 41 mL/100 g/min under oxygen to 203 ± 40 mL/100 g/min under carbogen. T1 decreased in both the cortex (from 1570 ± 164 to 1377 ± 72 ms, p < 0.05) and medulla (from 1788 ± 107 to 1573 ± 144 ms, p < 0.05) under carbogen relative to 100% oxygen. The results showed the potential of the use of ASL for perfusion quantification in mice and in models of renal diseases. Copyright © 2013 John Wiley & Sons, Ltd.
Concordance of BAI and BMI with DXA in the Newfoundland Population
Authors: Sun Guang , Cahill Farrell , Gulliver Wayne , Yi Yanqing , Xie Yagang , Bridger Tracey , Pace David , Zhang Hongwei
Published: April 2013

Background:

Body adiposity index (BAI), indirect method proposed to predict adiposity, was developed using Mexican Americans and very little data are available regarding its validation in Caucasian populations to date.

Objective:

The study objectives were to validate the BAI with dual‐energy X‐ray absorptiometry (DXA) body fat percentage (%BF), taking into consideration the gender and adiposity status.

Design and Methods:

A total of 2,601 subjects (Male 662, Female 1939) from our Complex Diseases in the Newfoundland population: Environment and Genetics (CODING) study participated in this investigation. Pearson correlations, with the entire cohort along with men and women separately, were used to compare the correlation of both BAI and BMI with %BF. Additionally, the concordance between BAI and BMI with %BF were also performed among normal‐weight (NW), overweight (OW), and obese (OB) groups. Adiposity status was determined by the Bray Criteria according to DXA %BF.

Results:

BAI performs better than BMI in our Caucasian population by: (1) reflecting the gender difference in total %BF between women and men, (2) correlating better with DXA %BF than BMI when women and men are combined, and (3) performing better in NW and OW subjects for both the sexes. However, BAI performs less effectively than BMI in OB men and women.

Conclusion:

In summary, the BAI method is a better estimate of adiposity than BMI in non‐OB subjects in our Caucasian population. A measurement sensitive to the changes in adiposity for both men and women is suggested to be incorporated into the present BAI equation to increase accuracy.
Sociodemographic, behavioral, and biological variables related to weight loss in native hawaiians and other pacific islanders
Authors: Kaholokula Joseph Keawe‘aimoku , Townsend Claire K.M. , Ige Arlene , Sinclair Ka‘imi A. , Mau Marjorie K. , Leake Anne , Palakiko Donna‐Marie , Yoshimura Sheryl R. , Kekauoha Puni , Hughes Claire
Published: April 2013

Objective:

Native Hawaiians and other Pacific Islanders (NHs/PIs) have a high obesity prevalence compared to other ethnic groups. We examined socio‐demographic, behavioral, and biological factors related to ≥3% weight loss in 100 overweight/obese NHs/PIs who completed a lifestyle intervention.

Design and Methods:

Data were from 56 Native Hawaiians, 22 Chuukese, and 22 Other Pacific Islanders who participated in a randomized controlled trial of the Partnership for Improving Lifestyle Intervention (PILI) 'Ohana Project. All completed a 3‐month weight loss program (WLP) to initiate weight loss and were then randomized into either a 6‐month family/community focused WLP called the PILI Lifestyle Program (PLP; n = 49) or a standard behavior WLP (SBP; n = 51). We collected baseline, 3‐ and 9‐month follow‐up data on socio‐demographics, weight (kg), a 6‐min. walk test, dietary fat, exercise frequency, and blood pressure.

Results and Conclusion:

Based on ANCOVA or logistic fit, ethnicity, sex, initial weight loss, fat in diet at baseline, change in systolic blood pressure, and intervention type were significantly associated (P ≤ .05) with ≥3% weight loss at 9‐month follow‐up. A logistic regression model indicated that Chuukese (OR = 6.04; CI = 1.14–32.17) and participants who had more weight loss in the first 3‐months (OR = 1.47; CI = 1.22–1.86) and who were in the PLP (OR = 4.50; CI = 1.50–15.14) were more likely to achieve ≥3% weight loss [model; χ2 (7, N = 100) = 45.50, P < .0001]. The same lifestyle intervention does not benefit all NHs/PIs equally, possibly due to differences in acculturation status and social support. The findings also point to the importance of initial weight loss to sustain motivation toward long‐term weight loss maintenance.
Psychosocial predictors of 4‐year BMI change in overweight and obese children in primary care
Authors: Incledon Emily , Gerner Bibi , Hay Margaret , Brennan Leah , Wake Melissa
Published: April 2013

Objective:

This study aimed to determine whether (1) initial and/or (2) changes in psychosocial functioning predict body mass index (BMI) z‐score change over 4 years in overweight/mildly obese 5‐ to 9‐year old children presenting to primary care.

Design and Methods:

Eligible participants (n = 258) were overweight/mildly obese children (IOTF criteria) recruited into the LEAP2 trial (ISRCTN52511065) from 3,958 children visiting general practitioners in Melbourne, Australia from May 2005 to July 2006. Predictors were change scores calculated from repeated measures of parent‐ and child‐reported child health‐related quality of life (PedsQL) and self‐esteem; child‐reported desire to be thinner; and parent‐reported child weight concern. Outcome was measured BMI z‐score change from baseline to 4 years.

Results:

The 189 respondents (61% female; 73% retention) showed little mean change in BMI z‐score (−0.08) but wide variation (standard deviation 0.50, range −1.32 to 1.20). Only one baseline measure (better parent‐reported PedsQL School Functioning) predicted improving BMI z‐score. However, parents and children consistently reported that changes in psychosocial functioning (i.e., PedsQL Social and Global Self‐esteem) were inversely related to BMI z‐score change scores. The strongest predictors of decreases in BMI z‐scores were changes in child‐reported body‐image variables, i.e., improvements in Physical Appearance Self‐esteem (β =0.40, 95% CI −0.98 to −0.15, P < 0.01) and declines in Desire to be Thinner (β = 0.33, 95% CI 0.04 to 0.23, P < 0.01).

Conclusions:

At presentation to primary care, it seems unlikely that targeting the psychosocial factors measured in this study would influence BMI z‐score change in overweight/mildly obese children. Subsequent change in psychosocial well‐being covaries with BMI z‐score change and may have important adolescent ramifications; the causal directions for these associations require further research.
Differences in motivations and weight loss behaviors in young adults and older adults in the national weight control registry
Authors: LaRose Jessica Gokee , Leahey Tricia M. , Hill James O. , Wing Rena R.
Published: April 2013

Objective:

The goal of this study was to compare young adults (YA) and older adults (OA) in the National Weight Control Registry on motivations for weight loss and weight‐loss behaviors.

Design and Methods:

Participants (n = 2,964, 82% female, 94% White, BMI = 24.8 ± 4.4) were divided into two age groups (18‐35 vs. 36‐50) and compared on motivations, strategies for weight loss, diet, physical activity (PA), and the three‐factor eating questionnaire.

Results:

YA were 28.6% of the sample (n = 848). YA and OA achieved similar weight losses (P = 0.38), but duration of maintenance was less in YA (43 vs. 58 months, P < 0.001). YA were more likely to cite appearance and social motivations for weight loss, were less motivated by health, and were less likely to report a medical trigger for weight loss (P's < 0.001). YA were more likely to use exercise classes and to lose weight on their own, and less likely to use a commercial program (P's < 0.001). YA reported engaging in more high‐intensity PA (P = 0.001). There were no group differences in total calories consumed (P = 0.47), or percent calories from fat (P = 0.97), alcohol (P = 0.52), or sugar‐sweetened beverages (P = 0.26).

Conclusions:

YA successful weight losers (SWL) are motivated more by appearance and social influences than OA, and physical activity appears to play an important role in their weight‐loss efforts. The differences reported by YA and OA SWL should be considered when developing weight‐loss programs for YA.
ERRγ enhances UCP1 expression and fatty acid oxidation in brown adipocytes
Authors: Dixen Karen , Basse Astrid L. , Murholm Maria , Isidor Marie S. , Hansen Lillian H. L. , Petersen M. Christine H. , Madsen Lise , Petrovic Natasa , Nedergaard Jan , Quistorff Bjørn , Hansen Jacob B.
Published: April 2013

Objective:

Estrogen‐related receptors (ERRs) are important regulators of energy metabolism. Here we investigated the hypothesis that ERRγ impacts on differentiation and function of brown adipocytes.

Design and Methods:

We characterize the expression of ERRγ in adipose tissues and cell models and investigate the effects of modulating ERR? activity on UCP1 gene expression and metabolic features of brown and white adipocytes.

Results:

ERRγ was preferentially expressed in brown compared to white fat depots, and ERRγ was induced during cold‐induced browning of subcutaneous white adipose tissue and brown adipogenesis. Overexpression of ERRγ positively regulated uncoupling protein 1 (UCP1) expression levels during brown adipogenesis. This ERRγ‐induced augmentation of UCP1 expression was independent of the presence of peroxisome proliferator‐activated receptor coactivator‐1 (PGC‐1α) but was associated with increased rates of fatty acid oxidation in adrenergically stimulated cells. ERR? did not influence mitochondrial biogenesis, and its reduced expression in white adipocytes could not explain their low expression level of UCP1.

Conclusions:

Through its augmenting effect on expression of UCP1, ERRγ may physiologically be involved in increasing the potential for energy expenditure in brown adipocytes, a function that is becoming of therapeutic interest.
Increased Smad signaling and reduced MRF expression in skeletal muscle from obese subjects
Authors: Watts Rani , McAinch Andrew J. , Dixon John B. , O'Brien Paul E. , Cameron‐Smith David
Published: April 2013

Objective:

The molecular mechanisms underpinning the loss of skeletal muscle mass and strength associated with insulin resistance remain to be extensively investigated. There is mounting recognition that certain ligands of the transforming growth factor (TGF)‐β family are upregulated in insulin resistant states, including obesity. This study analyses the expression of potent ligands of this family, TGF‐β1 and myostatin (MSTN) and downstream components of the canonical TGF‐β family signaling pathway (Smads) in skeletal muscle from lean and insulin resistant obese subjects.

Design and Methods:

Biopsies taken from the rectus abdominis muscle of lean (n = 13) and obese subjects (n = 20) were analyzed for the expression of TGF‐β1 and MSTN as well as TGF‐β signaling components, Smad2, 3, and 4, and transcription of the muscle regulatory factors (MRFs), MyoD and myogenin.

Results:

Increases in Smad2 and Smad3 phosphorylation, Smad4 and total Smad3 were observed to be coincident with altered transcription of MyoD and myogenin. TGF‐β1 and MSTN protein levels were not significantly altered.

Conclusion:

Thus, increased Smad signaling is likely to account for, at least, a proportion of obesity and insulin resistance‐related muscle atrophy through reduced MRF, particularly MyoD, transcription. The major regulatory ligand may not be MSTN and further members of the TGF‐β1 superfamily should be considered.
Longitudinal associations between BMI, waist circumference, and cardiometabolic risk in US youth: Monitoring implications
Authors: Jago R. , Mendoza J. A. , Chen T. , Baranowski T.
Published: April 2013

Objective:

This study examined whether change in body mass index (BMI) or waist circumference (WC) is associated with change in cardiometabolic risk factors and differences between cardiovascular disease specific and diabetes specific risk factors among adolescents. We also sought to examine any differences by gender or baseline body mass status.

Design:

The article is a longitudinal analysis of pre‐ and post‐data collected in the HEALTHY trial. Participants were 4,603 ethnically diverse adolescents who provided complete data at 6th and 8th grade assessments.

Methods:

The main outcome measures were percent change in the following cardiometabolic risk factors: fasting triglycerides, systolic and diastolic blood pressure, high density lipoprotein cholesterol, and glucose as well as a clustered metabolic risk score. Main exposures were change in BMI or WC z‐score. Models were run stratified by gender; secondary models were additionally stratified by baseline BMI group (normal, overweight, or obese).

Results:

Analysis showed that when cardiometabolic risk factors were treated as continuous variables, there was strong evidence (P < 0.001) that change in BMI z‐score was associated with change in the majority of the cardiovascular risk factors, except fasting glucose and the combined risk factor score for both boys and girls. There was some evidence that change in WC z‐score was associated with some cardiovascular risk factors, but change in WC z‐score was consistently associated with changes in fasting glucose.

Conclusions:

In conclusion, routine monitoring of BMI should be continued by health professionals, but additional information on disease risk may be provided by assessing WC.
Circulating regulatory T cells are reduced in obesity and may identify subjects at increased metabolic and cardiovascular risk
Authors: Wagner Nana‐Maria , Brandhorst Gunnar , Czepluch Frauke , Lankeit Mareike , Eberle Christoph , Herzberg Sebastian , Faustin Vivien , Riggert Joachim , Oellerich Michael , Hasenfuss Gerd , Konstantinides Stavros , Schäfer Katrin
Published: April 2013

Objective:

Reduced numbers of regulatory T (Treg) cells have been observed in visceral adipose tissue of obese mice and humans. However, it is unknown whether human obesity affects circulating Treg cells and whether their number is associated with markers of systemic inflammation or glucose intolerance.

Design and Methods:

Peripheral blood mononuclear cells were isolated from venous blood of obese (BMI ≥ 27 kg/m2; n = 30) and nonobese (BMI ≥ 27 kg/m2; n = 13) individuals and analyzed using flow cytometry for the expression of CD4, CD25, and Foxp3.

Results:

Reduced circulating Treg‐cell numbers were detected in obese compared with nonobese study participants (P = 0.038). Circulating CD4+CD25+CD127−Foxp3 Treg cells inversely correlated with body weight (P = 0.009), BMI (P = 0.004) and plasma leptin levels (P = 0.004) and were reduced in subjects with hsCRP ≥ 3.0 mg/L (P = 0.034) or HbA1c ≥ 5.5% (P < 0.005). Receiver operating characteristic curve analysis revealed a cutoff of circulating Treg cells < 1.06% to be predictive for hsCRP levels ≥ 3.0 mg/L, and logistic regression showed that the risk of having hsCRP levels ≥ 3.0 mg/L was increased 9.6‐fold (P = 0.008), if Treg cells were below this threshold. The Treg cutoff for HbA1c levels ≥ 5.5% was 0.73%, and this cutoff also predicted an increased risk of having elevated levels of both hsCRP and HbA1c, if only obese subjects were examined.

Conclusion:

Our findings thus reveal an association between circulating Treg cells and measures of adiposity, inflammation, and glucose intolerance. Although further prospective studies are needed, we present data suggesting that the determination of Treg cells might be useful to identify obese subjects at increased risk of developing cardiovascular and/or metabolic complications.
Pressuring and restrictive feeding styles influence infant feeding and size among a low‐income African‐American sample
Authors: Thompson Amanda L. , Adair Linda S. , Bentley Margaret E.
Published: April 2013

Objective:

The prevalence of overweight among infants and toddlers has increased dramatically in the past three decades, highlighting the importance of identifying factors contributing to early excess weight gain, particularly in high‐risk groups. Parental feeding styles and the attitudes and behaviors that characterize parental approaches to maintaining or modifying children's eating behavior are an important behavioral component shaping early obesity risk.

Design and Methods:

Using longitudinal data from the Infant Care and Risk of Obesity Study, a cohort study of 217 African‐American mother‐infant pairs with feeding styles, dietary recalls, and anthropometry collected from 3 to 18 months of infant age, we examined the relationship between feeding styles, infant diet, and weight‐for‐age and sum of skinfolds.

Results:

Longitudinal mixed models indicated that higher pressuring and indulgent feeding style scores were positively associated with greater infant energy intake, reduced odds of breastfeeding, and higher levels of age‐inappropriate feeding of liquids and solids, whereas restrictive feeding styles were associated with lower energy intake, higher odds of breastfeeding, and reduced odds of inappropriate feeding. Pressuring and restriction were also oppositely related to infant size with pressuring associated with lower infant weight‐for‐age and restriction with higher weight‐for‐age and sum of skinfolds. Infant size also predicted maternal feeding styles in subsequent visits indicating that the relationship between size and feeding styles is likely bidirectional.

Conclusion:

Our results suggest that the degree to which parents are pressuring or restrictive during feeding shapes the early feeding environment and, consequently, may be an important environmental factor in the development of obesity.
Moderate‐To‐vigorous physical activity is associated with decreases in body mass index from ages 9 to 15 years
Authors: Mitchell J. A. , Pate R. R. , España‐Romero V. , O'Neill J. R. , Dowda M. , Nader P. R.
Published: April 2013

Objective:

The purpose of this study is to determine whether time spent in objectively measured physical activity is associated with change in body mass index (BMI) from ages 9 to 15.

Design and Methods:

The participants were enrolled in the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (n = 938). At ages 9, 11, 12, and 15 the time spent in moderate‐to‐vigorous physical activity (MVPA) was objectively measured, and BMI was calculated (kg/m2). Longitudinal quantile regression was used to analyze the data. The 10th, 25th, 50th, 75th, and 90th BMI percentiles were modeled as the dependent variables with age and MVPA (h/day) modeled as predictors. Adjustment was also made for gender, race, sleep, healthy eating score, maternal education, and sedentary behavior.

Results:

A negative association between MVPA and change in BMI was observed at the 90th BMI percentile (−3.57, 95% CI −5.15 to −1.99 kg/m2 per hour of MVPA). The negative association between time spent in MVPA and change in BMI was progressively weaker toward the 10th BMI percentile (−0.27, 95% CI −0.62 to 0.07 kg/m2 per hour of MVPA). The associations remained similar after adjusting for the covariates, and when the analyses were stratified by gender.

Conclusion:

Time spent in MVPA was negatively associated with change in BMI from age 9 to 15. The association was strongest at the upper tail of the BMI distribution, and increasing time spent in MVPA could help reduce the prevalence of childhood obesity.
Effects of a lifestyle intervention on adiposity and fitness in overweight or low fit preschoolers (Ballabeina)
Authors: Niederer I. , Bürgi F. , Ebenegger V. , Marques‐Vidal P. , Schindler C. , Nydegger A. , Kriemler S. , Puder J. J.
Published: April 2013

Objective:

Overweight (OW) and low fit children represent cardiovascular high‐risk groups. A multidimensional school‐based lifestyle intervention performed in 652 preschoolers reduced skinfold thickness and waist circumference, and improved fitness, but did not affect BMI. The objective of this study is to examine whether the intervention was equally effective in OW (≥90th national percentile) and/or low fit (lowest sex‐ and age‐adjusted quartile of aerobic fitness) children compared to their normal weight and normal fit counterparts.

Design and Methods:

Cluster randomized controlled single blinded trial, conducted in 2008/09 in 40 randomly selected preschool classes in Switzerland. The intervention included a playful physical activity program and lessons on nutrition, media use and sleeps. Primary outcomes were BMI and aerobic fitness; secondary outcomes included sum of four skinfolds, waist circumference and motor agility. Modification of intervention effects by BMI‐group and fitness‐group was tested by interaction terms.

Results:

Compared to their counterparts, OW children (n = 130) had more beneficial effects on waist circumference (p for interaction = 0.001) and low fit children (n = 154) more beneficial effects on all adiposity outcomes (p for interaction ≤0.03). The intervention effects on both fitness outcomes were not modified by BMI‐ or fitness‐group (all p for interaction ≥0.2). Average intervention effect sizes for BMI were −0.12, −0.05, −0.26 and −0.02 kg/m2 and for aerobic fitness were 0.40, 0.30, 0.12 and 0.36 stages for OW, normal weight, low fit and normal fit children, respectively.

Conclusions: This multidimensional intervention was equally and for some adiposity measures even more effective in high‐risk preschoolers and represents a promising option for these children.
Aerobic exercise alone results in clinically significant weight loss for men and women: Midwest exercise trial 2
Authors: Donnelly Joseph E. , Honas Jeffery J. , Smith Bryan K. , Mayo Matthew S. , Gibson Cheryl A. , Sullivan Debra K. , Lee Jaehoon , Herrmann Stephen D. , Lambourne Kate , Washburn Rik A.
Published: April 2013

Exercise is recommended by public health agencies for weight management; however, the role of exercise is generally considered secondary to energy restriction. Few studies exist that have verified completion of exercise, measured the energy expenditure of exercise, and prescribed exercise with equivalent energy expenditure across individuals and genders.

Objective:

The objective of this study was to evaluate aerobic exercise, without energy restriction, on weight loss in sedentary overweight and obese men and women.

Design and Methods:

This investigation was a randomized, controlled, efficacy trial in 141 overweight and obese participants (body mass index, 31.0 ± 4.6 kg/m2; age 22.6 ± 3.9 years). Participants were randomized (2:2:1 ratio) to exercise at either 400 kcal/session or 600 kcal/session or to a nonexercise control. Exercise was supervised, 5 days/week, for 10 months. All participants were instructed to maintain usual ad libitum diets. Because of the efficacy design, completion of ≥90% of exercise sessions was an a priori definition of per protocol, and these participants were included in the analysis.

Results:

Weight loss from baseline to 10 months for the 400 and 600 kcal/session groups was 3.9 ± 4.9 kg (4.3%) and 5.2 ± 5.6 kg (5.7%), respectively, compared with weight gain for controls of 0.5 ± 3.5 kg (0.5%) (P < 0.05). Differences for weight loss from baseline to 10 months between the exercise groups and differences between men and women within groups were not statistically significant.

Conclusions:

Supervised exercise, with equivalent energy expenditure, results in clinically significant weight loss with no significant difference between men and women.
Greater screen time is associated with adolescent obesity: A longitudinal study of the BMI distribution from Ages 14 to 18
Authors: Mitchell Jonathan A. , Rodriguez Daniel , Schmitz Kathryn H. , Audrain‐McGovern Janet
Published: April 2013

Objective:

Previous research has examined the association between screen time and average changes in adolescent body mass index (BMI). Until now, no study has evaluated the longitudinal relationship between screen time and changes in the BMI distribution across mid to late adolescence.

Design and Methods:

Participants (n = 1,336) were adolescents who were followed from age 14 to age 18 and surveyed every 6 months. Time spent watching television/videos and playing video games was self‐reported (<1 h day−1, 1 h day−1, 2 h day−1, 3 h day−1, 4 h day−1, or 5+ h day−1). BMI (kg m−2) was calculated from self‐reported height and weight. Longitudinal quantile regression was used to model the 10th, 25th, 50th, 75th, and 90th BMI percentiles as dependent variables. Study wave and screen time were the main predictors, and adjustment was made for gender, race, maternal education, hours of sleep, and physical activity.

Results:

Increases at all the BMI percentiles over time were observed, with the greatest increase observed at the 90th BMI percentile. Screen time was positively associated with changes in BMI at the 50th (0.17, 95% CI: 0.06, 0.27), 75th (0.31, 95% CI: 0.10, 0.52), and 90th BMI percentiles (0.56, 95% CI: 0.27, 0.82). No associations were observed between screen time and changes at the 10th and 25th BMI percentiles.

Conclusions:

Positive associations between screen time and changes in the BMI at the upper tail of the BMI distribution were observed. Therefore, lowering screen time, especially among overweight and obese adolescents, could contribute to reducing the prevalence of adolescent obesity.
Associations of testosterone and sex hormone binding globulin with adipose tissue hormones in midlife women
Authors: Wildman Rachel P. , Wang Dan , Fernandez Ivonne , Mancuso Peter , Santoro Nanette , Scherer Philipp E. , Sowers MaryFran R.
Published: April 2013

Objective:

Regulators of adipose tissue hormones remain incompletely understood, but may include sex hormones. As adipose tissue hormones have been shown to contribute to numerous metabolic and cardiovascular disorders, understanding their regulation in midlife women is of clinical importance. Therefore, we assessed the associations between testosterone (T) and sex hormone binding globulin (SHBG) with leptin, high molecular weight (HMW) adiponectin, and the soluble form of the leptin receptor (sOB‐R) in healthy midlife women.

Design and Methods:

Cross‐sectional analyses were performed using data from 1,881 midlife women (average age 52.6 (±2.7) years) attending the sixth Annual follow‐up visit of the multiethnic Study of Women's Health Across the Nation.

Results:

T was weakly negatively associated with both HMW adiponectin and sOB‐R (r = −0.12 and r = −0.10, respectively; P < 0.001 for both), and positively associated with leptin (r = 0.17; P < 0.001). SHBG was more strongly and positively associated with both HMW adiponectin and sOB‐R (r = 0.29 and r = 0.24, respectively; P < 0.001 for both), and more strongly and negatively associated with leptin (r = −0.27; P < 0.001). Adjustment for fat mass, insulin resistance, or waist circumference only partially diminished associations with HMW adiponectin and sOB‐R, but attenuated associations with leptin. In conclusion, in these midlife women, lower SHBG values, and to a lesser extent, higher T levels, were associated with lower, or less favorable, levels of adiponectin and sOB‐R, independent of fat mass.

Conclusions:

These data suggest that variation in these adipose hormones resulting from lower SHBG levels, and possibly, though less likely, greater androgenicity, may contribute to susceptibility for metabolic and cardiovascular outcomes during midlife in women.
The association between self‐reported sleep quality and overweight in a Chinese population
Authors: Hung Hao‐Chang , Yang Yi‐Ching , Ou Horng‐Yih , Wu Jin‐Shang , Lu Feng‐Hwa , Chang Chih‐Jen
Published: April 2013

Objective:

Sleep quality and obesity are associated with type 2 diabetes, hypertension, and metabolic syndrome. However, there is limited research on the association between sleep quality and obesity, and thus the aim of this study is to investigate this relationship in a Chinese population.

Design and Methods:

Subjects were recruited from the Prevention Health Center of National Cheng Kung University Hospital. Anthropometric data and metabolic parameters were measured. Being overweight or obese was defined according to the recommendations of the Department of Health in Taiwan. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI).

Results:

Of the total 2,803 subjects, 1,059 were classified as normal weight, 1,127 were overweight, and 617 were obese. The global PSQI score were 6.30 ± 2.56, 6.61 ± 2.96, and 7.02 ± 2.95 in subjects who were normal weight, overweight, and obese, respectively (test for trend, P < 0.001). Of the variables tested in the multivariate linear regression model, female gender, being overweight, obesity, sleep duration, and alcohol drinking were significantly associated with global PSQI scores, and in the multivariate logistic regression model, female gender, being overweight, obesity, and sleep duration were independent predictors of poor sleepers after controlling for age, gender, BMI or different weight statuses, sleep duration, alcohol drinking, smoking, habitual exercise, hypertension, newly diagnosed diabetes, total cholesterol, high‐density lipoprotein, triglyceride, estimated glomerular filtration rate, and alanine aminotransferase.

Conclusions:

In conclusion, female gender, being overweight, obesity, and sleep duration were associated with poor sleep quality independent of cardiometabolic risk factors. In clinical practice, subjects who are obese, or even only overweight, should be evaluated for the presence of sleep disturbance.