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1.  Evaluation of Partial k-space strategies to speed up Time-domain EPR Imaging 
Narrow-line spin probes derived from the trityl radical have led to the development of fast in vivo time-domain EPR imaging. Pure phase-encoding imaging modalities based on the Single Point Imaging scheme (SPI) have demonstrated the feasibility of 3D oximetric images with functional information in minutes. In this paper, we explore techniques to improve the temporal resolution and circumvent the relatively short biological half-lives of trityl probes using partial k-space strategies. There are two main approaches: one involves the use of the Hermitian character of the k-space by which only part of the k-space is measured and the unmeasured part is generated using the Hermitian symmetry. This approach is limited in success by the accuracy of numerical estimate of the phase roll in the k-space that corrupts the Hermiticy. The other approach is to measure only a judicially chosen reduced region of k-space (a centrosymmetric ellipsoid region) that more or less accounts for >70% of the k-space energy. Both of these aspects were explored in FT-EPR imaging with a doubling of scan speed demonstrated by considering ellipsoid geometry of the k-space. Partial k-space strategies help improve the temporal resolution in studying fast dynamics of functional aspects in vivo with infused spin probes.
PMCID: PMC3548084  PMID: 23045171
MRI; Time-domain EPR imaging; Partial Fourier; partial k-space acquisition; conjugate symmetry; Single Point Imaging; homodyne detection; projection onto convex sets (POCS)
2.  Short-term Preoperative Dietary Restriction Is Neuroprotective in a Rat Focal Stroke Model 
PLoS ONE  2014;9(4):e93911.
Stroke is a major complication of cardiovascular surgery, resulting in over 100,000 deaths and over a million postoperative encephalopathies annually in the US and Europe. While mitigating damage from stroke after it occurs has proven elusive, opportunities to reduce the incidence and/or severity of stroke prior to surgery in at-risk individuals remain largely unexplored. We tested the potential of short-term preoperative dietary restriction to provide neuroprotection in rat models of focal stroke. Rats were preconditioned with either three days of water-only fasting or six days of a protein free diet prior to induction of transient middle cerebral artery occlusion using two different methods, resulting in either a severe focal stroke to forebrain and midbrain, or a mild focal stroke localized to cortex only. Infarct volume, functional recovery and molecular markers of damage and protection were assessed up to two weeks after reperfusion. Preoperative fasting for 3 days reduced infarct volume after severe focal stroke. Neuroprotection was associated with modulation of innate immunity, including elevation of circulating neutrophil chemoattractant C-X-C motif ligand 1 prior to ischemia and suppression of striatal pro-inflammatory markers including tumor necrosis factor α, its receptor and downstream effector intercellular adhesion molecule-1 after reperfusion. Similarly, preoperative dietary protein restriction for 6 days reduced ischemic injury and improved functional recovery in a milder cortical infarction model. Our results suggest that short-term dietary restriction regimens may provide simple and translatable approaches to reduce perioperative stroke severity in high-risk elective vascular surgery.
PMCID: PMC3976327  PMID: 24705386
3.  The Role of Eating and Emotion in Binge Eating Disorder and Loss of Control Eating 
Binge eating, defined as the consumption of large amounts of food during which a sense of loss of control is experienced, is associated with negative affect. However, there are no data on the experience of loss of control after accounting for the effects of negative affect and caloric intake.
Nine adult patients with binge eating disorder (BED) and 13 obese non-BED (NBED) participants carried a palmtop computer for seven days, rating momentary mood and sense of loss of control multiple times each day. Electronic food logs were collected once daily.
After removing the effects of caloric intake and negative affect, a significant group difference was observed for ratings of loss of control between BED and NBED participants.
These findings suggest the experience of loss of control in adults with BED is a salient feature of binge episodes, beyond that explained by caloric intake and momentary affect.
PMCID: PMC3570734  PMID: 23109227
4.  Evaluation of the Lymphocyte Trafficking Drug FTY720 in Vaginal Tissues 
Journal of medical primatology  2013;42(2):89-100.
FTY720 is an immunomodulatory agent that reduces lymphocytes in peripheral tissues and circulation. Such agents may be effective as vaginal microbicides for HIV prevention. Systemic or vaginal application of FTY720 may reduce lymphocyte concentrations in genital tissues, reducing HIV target cell numbers.
Five female pigtail macaques received topical vaginal gel FTY720 (n=2), intravenous (IV) FTY720 (n=2), or placebo gel (n=1) in this pilot study. Circulating and mucosal lymphocytes and genital mucosa, cytokines, and tissue histology were analyzed to document topical and IV FTY720 effects.
Topical and IV FTY720 appeared to decrease levels of cervicovaginal IL-8, IL-1ra, and genital inflammatory cells. Small sample size precluded statistical analysis. Topical administration had no overt adverse effects.
This study introduces FTY720 as an immunomodulatory agent for the vaginal mucosa, compares topical effects to those of IV administration, and provides the basis for future studies involving FTY720 for HIV prevention.
PMCID: PMC3594332  PMID: 23311598
Genital; nonhuman primates; topical gel; HIV
A significant number of post-bariatric surgery patients present with eating disorders (ED) symptoms that require specialized treatment. These cases are thought to be underreported due to their frequent sub-syndromal presentation. This paper describes eating disorder syndromes that develop subsequent to bariatric surgery.
The clinical charts of 12 individuals who were hospitalized on a specialized inpatient eating disorders unit were reviewed.
Based on the new DSM-5 proposed criteria, six patients would meet criteria for an anorexia nervosa (AN) diagnosis: three with binge eating/purge AN subtype and three with restrictive AN subtype. An additional four met criteria for atypical anorexia nervosa, since they were at a normal weight, and two patients met criteria for bulimia nervosa.
Several similarities to the classical EDs were found. The findings that most distinguished these patients from those with classical EDs were their ages, and the age of onset of the ED for some patients.
PMCID: PMC3596455  PMID: 23192683
bariatric surgery; post surgery eating disorders; DSM-5
7.  Pre-Operative Diet Impacts the Adipose Tissue Response to Surgical Trauma 
Surgery  2012;153(4):584-593.
Short-term changes in pre-operative nutrition can have profound effects on surgery related outcomes such as ischemia reperfusions injury in pre-clinical models. Dietary interventions that lend protection against stress in animal models (e.g. fasting, dietary restriction [DR]) impact adipose tissue quality/quantity. Adipose tissue holds high surgical relevance due to its anatomic location and high tissue volume, and it is ubiquitously traumatized during surgery. Yet the response of adipose tissue to trauma under clinically relevant circumstances including dietary status remains poorly defined. We hypothesized that pre-operative diet alters the adipose tissue response to surgical trauma.
A novel mouse model of adipose tissue surgical trauma was employed. Dietary conditions (diet induced obesity [DIO], pre-operative DR) were modulated prior to application of surgical adipose tissue trauma in the context of clinically common scenarios (different ages, simulated bacterial wound contamination). Local/distant adipose tissue phenotypic responses were measured as represented by gene expression of inflammatory, tissue remodeling/growth, and metabolic markers.
Surgical trauma had a profound effect on adipose tissue phenotype at the site of trauma. Milder but significant distal effects on non-traumatized adipose tissue were also observed. DIO exacerbated the inflammatory aspects of this response, and pre-operative DR tended to reverse these changes. Age and LPS-simulated bacterial contamination also impacted the adipose tissue response to trauma, with young adult animals and LPS treatment exacerbating the proinflammatory response.
Surgical trauma dramatically impacts both local and distal adipose tissue biology. Short-term pre-operative DR may offer a strategy to attenuate this response.
PMCID: PMC3603342  PMID: 23274098
8.  Erythropoietic Defect Associated with Reduced Cell Proliferation in Mice Lacking the 26S Proteasome Shuttling Factor Rad23b 
Molecular and Cellular Biology  2013;33(19):3879-3892.
Rad23a and Rad23b proteins are linked to nucleotide excision DNA repair (NER) via association with the DNA damage recognition protein xeroderma pigmentosum group C (XPC) are and known to be implicated in protein turnover by the 26S proteasome. Rad23b-null mice are NER proficient, likely due to the redundant function of the Rad23b paralogue, Rad23a. However, Rad23b-null midgestation embryos are anemic, and most embryos die before birth. Using an unbiased proteomics approach, we found that the majority of Rad23b-interacting partners are associated with the ubiquitin-proteasome system (UPS). We tested the requirement for Rad23b-dependent UPS activity in cellular proliferation and more specifically in the process of erythropoiesis. In cultured fibroblasts derived from embryos lacking Rad23b, proliferation rates were reduced. In fetal livers of Rad23b-null embryos, we observed reduced proliferation, accumulation of early erythroid progenitors, and a block during erythroid maturation. In primary wild-type (WT) erythroid cells, knockdown of Rad23b or chemical inhibition of the proteasome reduced survival and differentiation capability. Finally, the defects linked to Rad23b loss specifically affected fetal definitive erythropoiesis and stress erythropoiesis in adult mice. Together, these data indicate a previously unappreciated requirement for Rad23b and the UPS in regulation of proliferation in different cell types.
PMCID: PMC3811862  PMID: 23897431
9.  Temporal Sequence of Comorbid Alcohol Use Disorder and Anorexia Nervosa 
Addictive behaviors  2012;38(3):1704-1709.
Women with eating disorders have a significantly higher prevalence of substance use disorders than the general population. The goal of the current study was to assess the temporal pattern of comorbid anorexia nervosa (AN) and alcohol use disorder (AUD) and the impact this ordering has on symptomatology and associated features. Women were placed into one of three groups based on the presence or absence of comorbid AUD and the order of AN and AUD onset in those with both disorders: (1) AN Only, (2) AN First, and (3) AUD First. The groups were compared on psychological symptoms and personality characteristics often associated with AN, AUD, or both using general linear models. Twenty-one percent of women (n = 161) with AN reported a history of AUD with 115 reporting AN onset first and 35 reporting AUD onset first. Women with binge-eating and/or purging type AN were significantly more likely to have AUD. In general, differences were found only between women with AN Only and women with AN and AUD regardless of order of emergence. Women with AN and AUD had higher impulsivity scores and higher prevalence of depression and borderline personality disorder than women with AN Only. Women with AN First scored higher on traits commonly associated with AN, whereas women with comorbid AN and AUD displayed elevations in traits more commonly associated with AUD. Results do not indicate a distinct pattern of symptomatology in comorbid AN and AUD based on the temporal sequence of the disorders.
PMCID: PMC3558554  PMID: 23254222
anorexia nervosa; alcohol use disorder; comorbidity; age of onset
10.  Moderators of Post-Binge Eating Negative Emotion in Eating Disorders 
Journal of psychiatric research  2012;47(3):323-328.
The purpose of this study was to test the impact of two variables on post-binge eating negative emotion in a combined sample of women with anorexia nervosa (AN; n = 47) and bulimia nervosa (BN; n = 121). Participants completed two weeks of an ecological momentary assessment protocol during which they provided multiple daily ratings of overall negative affect and guilt and reported eating disorder behaviors including binge eating and self-induced vomiting. The results indicate that both overall negative affect and guilt exhibited a statistically significantly decrease in the hour immediately following binge eating episodes. The decrease in guilt, but not overall negative affect, was moderated by eating disorder diagnosis and the tendency to engage in self-induced vomiting. Specifically, individuals with BN reported a greater reduction in guilt than those with AN, and individuals who did not typically engage in self-induced vomiting reported more decreases in guilt than those who typically engaged in self-induced vomiting. This study extends the existing literature on the relationship between negative affect and eating disorder behaviors, suggesting guilt as a potentially relevant facet of negative affect in the maintenance of binge eating. In addition, the findings indicate that two individual differences, eating disorder diagnosis and self-induced vomiting, may influence the trajectory of guilt following binge eating episodes.
PMCID: PMC3570645  PMID: 23245289
anorexia nervosa; bulimia nervosa; negative affect; guilt; ecological momentary assessment
11.  Trait-level and momentary correlates of bulimia nervosa with a history of anorexia nervosa 
Some investigators have suggested subtyping bulimia nervosa (BN) by anorexia nervosa (AN) history. We examined trait-level and momentary eating-related and psychosocial factors in BN with and without an AN history.
Interview, questionnaire, and ecological momentary assessment data of eating-related and psychological symptoms were collected from 122 women with BN, including 43 with (BN+) and 79 without an AN history (BN−).
Body mass index (kg/m2) was lower in BN+ than BN− (p=.001). Groups did not differ on trait-level anxiety, shape/weight concerns, psychiatric comorbidity, or dietary restraint; or on momentary anxiety, dietary restriction, binge eating, purging, or exercise frequency, or affective patterns surrounding binge/purge behaviors. Negative affect increased prior to exercise and decreased thereafter in BN+ but not BN−, although groups did not statistically differ.
Results do not support formally subtyping BN by AN history. Exercise in BN+ may modulate negative affect, which could have important treatment implications.
PMCID: PMC3570735  PMID: 22987478
eating disorders; bulimia nervosa; history of anorexia nervosa; subtyping; classification; exercise
12.  Stable Isotope- and Mass Spectrometry-based Metabolomics as Tools in Drug Metabolism: A Study Expanding Tempol Pharmacology 
Journal of proteome research  2013;12(3):1369-1376.
The application of mass spectrometry-based metabolomics in the field of drug metabolism has yielded important insights not only into the metabolic routes of drugs but has provided unbiased, global perspectives of the endogenous metabolome that can be useful for identifying biomarkers associated with mechanism of action, efficacy, and toxicity. In this report, a stable isotope- and mass spectrometry-based metabolomics approach that captures both drug metabolism and changes in the endogenous metabolome in a single experiment is described. Here the antioxidant drug tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl) was chosen because its mechanism of action is not completely understood and its metabolic fate has not been studied extensively. Furthermore, its small size (MW = 172.2) and chemical composition (C9H18NO2) makes it challenging to distinguish from endogenous metabolites. In this study, mice were dosed with tempol or deuterated tempol (C9D17HNO2) and their urine profiled using ultraperformance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Principal component analysis of the urinary metabolomics data generated a Y-shaped scatter plot containing drug metabolites (protonated and deuterated) that were clearly distinct from the endogenous metabolites. Ten tempol drug metabolites, including eight novel metabolites, were identified. Phase II metabolism was the major metabolic pathway of tempol in vivo, including glucuronidation and glucosidation. Urinary endogenous metabolites significantly elevated by tempol treatment included 2,8-dihydroxyquinoline (8.0-fold, P<0.05) and 2,8-dihydroxyquinoline-β-D-glucuronide (6.8-fold, P<0.05). Urinary endogenous metabolites significantly attenuated by tempol treatment including pantothenic acid (1.3-fold, P<0.05) and isobutrylcarnitine (5.3-fold, P<0.01). This study underscores the power of a stable isotope- and mass spectrometry-based metabolomics in expanding the view of drug pharmacology.
PMCID: PMC3594779  PMID: 23301521
Tempol; Stable Isotope; Metabolomics; Mass spectrometry; Drug Metabolism
13.  Associations between physical activity and mental health among bariatric surgical candidates 
Journal of psychosomatic research  2013;74(2):161-169.
This study aimed to examine associations between physical activity (PA) and mental health among adults undergoing bariatric surgery.
Cross sectional analysis was conducted on pre-operative data of 850 adults with ≥ class 2 obesity. PA was measured with a step activity monitor; mean daily steps, active minutes, and high-cadence minutes (proxy for moderate-vigorous intensity PA) were determined. Mental health functioning, depressive symptoms and treatment for depression or anxiety were measured with the Medical Outcomes Study 36-item Short Form, Beck Depression Inventory, and a study-specific questionnaire, respectively. Logistic regression analyses tested associations between PA and mental health indicators, controlling for potential confounders. Receiver operative characteristic analysis determined PA thresholds that best differentiated odds of each mental health indicator.
Each PA parameter was significantly (P<.05) associated with a decreased odds of depressive symptoms and/or treatment for depression or anxiety, but not with impaired mental health functioning. After controlling for sociodemographics and physical health, only associations with treatment for depression and anxiety remained statistically significant. PA thresholds that best differentiated those who had vs. had not recently received treatment for depression or anxiety were <191 active minutes/day, <4750 steps/day, and <8 high-cadence minutes/day. Utilizing high-cadence minutes, compared to active minutes or steps, yielded the highest classification accuracy.
Adults undergoing bariatric surgery who meet relatively low thresholds of PA (e.g., ≥ 8 high-cadence minutes/day, representative of approximately one hour/week of moderate-vigorous intensity PA) are less likely to have recently received treatment for depression or anxiety compared to less active counterparts.
PMCID: PMC3556899  PMID: 23332532
anxiety; bariatric surgery; depressive symptoms; exercise; Roux-en-Y gastric bypass; severe obesity
14.  Lack of Prophylactic Efficacy of Oral Maraviroc in Macaques despite High Drug Concentrations in Rectal Tissues 
Journal of Virology  2013;87(16):8952-8961.
Maraviroc (MVC) is a potent CCR5 coreceptor antagonist that is in clinical testing for daily oral pre-exposure prophylaxis (PrEP) for HIV prevention. We used a macaque model consisting of weekly SHIV162p3 exposures to evaluate the efficacy of oral MVC in preventing rectal SHIV transmission. MVC dosing was informed by the pharmacokinetic profile seen in blood and rectal tissues and consisted of a human-equivalent dose given 24 h before virus exposure, followed by a booster postexposure dose. In rectal secretions, MVC peaked at 24 h (10,242 ng/ml) with concentrations at 48 h that were about 40 times those required to block SHIV infection of peripheral blood mononuclear cells (PBMCs) in vitro. Median MVC concentrations in rectal tissues at 24 h (1,404 ng/g) were 30 and 10 times those achieved in vaginal or lymphoid tissues, respectively. MVC significantly reduced macrophage inflammatory protein 1β-induced CCR5 internalization in rectal mononuclear cells, an indication of efficient binding to CCR5 in rectal lymphocytes. The half-life of CCR5-bound MVC in PBMCs was 2.6 days. Despite this favorable profile, 5/6 treated macaques were infected during five rectal SHIV exposures as were 3/4 controls. MVC treatment was associated with a significant increase in the percentage of CD3+/CCR5+ cells in blood. We show that high and durable MVC concentrations in rectal tissues are not sufficient to prevent SHIV infection in macaques. The increases in CD3+/CCR5+ cells seen during MVC treatment point to unique immunological effects of CCR5 inhibition by MVC. The implications of these immunological effects on PrEP with MVC require further evaluation.
PMCID: PMC3754060  PMID: 23740994
15.  Sub-diffraction Laser Synthesis of Silicon Nanowires 
Scientific Reports  2014;4:3908.
We demonstrate synthesis of silicon nanowires of tens of nanometers via laser induced chemical vapor deposition. These nanowires with diameters as small as 60 nm are produced by the interference between incident laser radiation and surface scattered radiation within a diffraction limited spot, which causes spatially confined, periodic heating needed for high resolution chemical vapor deposition. By controlling the intensity and polarization direction of the incident radiation, multiple parallel nanowires can be simultaneously synthesized. The nanowires are produced on a dielectric substrate with controlled diameter, length, orientation, and the possibility of in-situ doping, and therefore are ready for device fabrication. Our method offers rapid one-step fabrication of nano-materials and devices unobtainable with previous CVD methods.
PMCID: PMC3904146  PMID: 24469704
16.  PI3K-mTOR inhibitor PF-04691502 anti-tumor activity is enhanced with induction of wild-type TP53 in human xenograft and murine knockout models of head and neck cancer 
PI3K-mTOR pathway activation is often associated with altered expression or mutations of PIK3CA, TP53/p73, PTEN and TGFβR in head and neck squamous cell carcinomas (HNSCC). However, little is known about how these alterations affect response to PI3K-mTOR targeted agents.
Experimental Design
In this preclinical study, PI3K-Akt-mTOR signaling was characterized in 9 HNSCC (UM-SCC) cell lines and Human Oral Keratinocytes (HOK). We investigated the molecular and anti-cancer effects of dual PI3K/mTOR inhibitor PF-04691502(PF-502) in UM-SCC expressing PIK3CA with decreased wtTP53, mtTP53-/+mtTGFβR2, and in HNSCC of a conditional Pten/Tgfbr1 double knockout (2cKO) mouse model, displaying PI3K-Akt-mTOR activation.
UM-SCC showed increased PIK3CA expression and Akt/mTOR activation, and PF-502 inhibited PI3K/mTORC1/2 targets. In human HNSCC expressing PIK3CA and decreased wtTP53 and p73, PF-502 reciprocally enhanced TP53/p73 expression and growth inhibition, which was partially reversible by p53 inhibitor pifithrin-α. Most UM-SCC with wtTP53 exhibited a lower IC50 than those with mtTP53 status. PF-502 blocked growth in G0/G1 and increased apoptotic subG0 DNA. PF502 suppressed tumorigenesis and showed combinatorial activity with radiation in a wtTP53 UMSCC xenograft model. PF-502 also significantly delayed HNSCC tumorigenesis and prolonged survival of Pten/Tgfbr1 deficient mice. Significant inhibition of p-Akt, p-4EBP1, p-S6, Ki67, as well as increased p53 and TUNEL were observed in tumor specimens.
PI3K-mTOR inhibition can enhance TP53/p73 expression and significantly inhibit tumor growth alone or when combined with radiation in HNSCC with wtTP53. PIK3CA, TP53/p73, PTEN and TGFβ alterations are potential modifiers of response and merit investigation in future clinical trials with PI3K-mTOR inhibitors.
PMCID: PMC3715575  PMID: 23640975
PF-04691502; PI3K/mTOR inhibition; TP53; Pten Tgfbr1 knockout mice; head and neck cancer
17.  Far-field Imaging of Non-fluorescent Species with Sub-diffraction Resolution 
Nature photonics  2013;7:449-453.
Super-resolution optical microscopy is opening a new window to unveil the unseen details on the nanoscopic scale. Current far-field super-resolution techniques rely on fluorescence as the read-out1–5. Here, we demonstrate a scheme for breaking the diffraction limit in far-field imaging of non-fluorescent species by using spatially controlled saturation of electronic absorption. Our method is based on a pump-probe process where a modulated pump field perturbs the charge-carrier density in a sample, thus modulating the transmission of a probe field. A doughnut shape laser beam is then added to transiently saturate the electronic transition in the periphery of the focal volume, thus the induced modulation in the sequential probe pulse only occurs at the focal center. By raster scanning the three collinearly aligned beams, high-speed sub-diffraction-limited imaging of graphite nano-platelets was performed. This technique potentially enables super-resolution imaging of nano-materials and non-fluorescent chromophores, which may remain out of reach for fluorescence-based methods.
PMCID: PMC3891596  PMID: 24436725
18.  Posttraumatic Stress Disorder as a Moderator of the Association Between Negative Affect and Bulimic Symptoms: An Ecological Momentary Assessment Study 
Comprehensive psychiatry  2012;54(1):61-69.
The purpose of this study was to examine the potential moderating effect of posttraumatic stress disorder (PTSD) on the emotion-behavior relationship in individuals with bulimia nervosa (BN).
A total of 119 women with BN were involved in the study. Participants were divided into two groups: those with BN and PTSD (n = 20), and those with BN only (n = 99). Ecological momentary assessment (EMA) procedures were utilized for the examination of affect, frequency of bulimic behaviors, and the relationship of affect and bulimic behavior over time. The Structured Clinical Interview for DSM-IV Axis I Disorders was conducted for the diagnosis of BN, PTSD, mood disorders, anxiety disorders, and substance use disorders. Mood disorders, anxiety disorders, and substance use disorders functioned as covariates in all analyses.
Statistical models showed that those in the PTSD group reported a greater daily mean level of negative affect and a greater daily frequency of bulimic behaviors than those in the BN only group. Moderation was found for the association between negative affect and time in that the PTSD group showed a faster acceleration in negative affect prior to purging and faster deceleration in negative affect following purging. The association between positive affect and time was also moderated by group, indicating that the PTSD group had a faster acceleration in positive affect after purging than the BN only group.
These findings highlight the importance of recognizing PTSD when interpreting the emotion-behavior relationship in individuals with BN.
PMCID: PMC3473110  PMID: 22789761
Posttraumatic stress disorder; Bulimia nervosa; Palm top computers
19.  Moderators of the Association Between Exercise Identity and Obligatory Exercise Among Participants of an Athletic Event 
Body image  2012;10(1):70-77.
Previous research has connected exercise identity with obligatory exercise, yet to date no empirical studies have identified moderator variables of this association. The current study included participants of an athletic event (full marathon, n = 582; half marathon, n = 1,106; shorter distance, n = 733) who completed questionnaires about exercise behaviors, obligatory exercise, and internalization of both the thin-ideal and athletic-ideal body shapes. General linear model analyses were conducted to examine the exercise identity-obligatory exercise relationship; moderator variables included gender, internalization of the thin-ideal body shape, and internalization of the athletic-ideal body shape. After controlling for the effects of body mass index, age, and distance group, the three-way interaction of exercise identity, gender, and internalization of the athletic-ideal body shape predicted obligatory exercise. Findings suggest that women who report high identification with exercise and high value on having an athletic physique may be vulnerable to obligatory exercise.
PMCID: PMC3534926  PMID: 23092850
exercise identity; obligatory exercise; internalization
20.  DSM-IV-Defined Anorexia Nervosa Versus Subthreshold Anorexia Nervosa (EDNOS-AN) 
Eating disorder not otherwise specified (EDNOS) is the most prevalent eating disorder, yet its heterogeneity begs less reliance on this broad diagnostic category. The purpose of this study was to compare women with anorexia nervosa (AN) and EDNOS, AN type (EDNOS-AN) from a multisite study on eating-related and general psychopathology measures.
One hundred eighteen participants (n = 59 with DSM-IV AN, n = 59 with EDNOS-AN) completed structured interviews, questionnaires and a physical examination at baseline. In addition, participants carried a handheld palm pilot computer for two weeks to provide ecological momentary assessment (EMA) information about mood and eating disorder behaviors.
No significant differences between AN and EDNOS-AN were found on the self-report and interview measures, or on the EMA mood assessments. The only differences to emerge were that participants with AN reported higher rates of binge eating and purging on EMA compared to those with EDNOS-AN, while EDNOS-AN reported higher rates of checking thighs and joints on EMA compared to those with AN. For the physiological parameters, AN presented with lower white blood cell counts compared to EDNOS-AN.
Findings highlight the clinical significance of EDNOS-AN, and support a closer look at the definition of AN as proposed by DSM-5.
PMCID: PMC3715616  PMID: 22847947
Anorexia nervosa; EDNOS; classification
21.  Subjective and Objective Binge Eating in Relation to Eating Disorder Symptomatology, Negative Affect, and Personality Dimensions 
The International journal of eating disorders  2012;46(1):10.1002/eat.22066.
The current study explored the clinical meaningfulness of distinguishing subjective (SBE) from objective binge eating (OBE) among individuals with threshold/subthreshold bulimia nervosa (BN). We examined relations between OBEs and SBEs and eating disorder symptoms, negative affect, and personality dimensions using both a group comparison and a continuous approach.
Participants were 204 adult females meeting criteria for threshold/subthreshold BN who completed questionnaires related to disordered eating, affect, and personality.
Group comparisons indicated that SBE and OBE groups did not significantly differ on eating disorder pathology or negative affect, but did differ on two personality dimensions (cognitive distortion and attentional impulsivity). Using the continuous approach, we found that frequencies of SBEs (not OBEs) accounted for unique variance in weight/shape concern, diuretic use frequency, depressive symptoms, anxiety, social avoidance, insecure attachment, and cognitive distortion.
SBEs in the context of BN may indicate broader areas of psychopathology.
PMCID: PMC3832259  PMID: 23109272
subjective binge eating; objective binge eating; affect; personality; bulimia nervosa
22.  Sustainable remediation: electrochemically assisted microbial dechlorination of tetrachloroethene-contaminated groundwater 
Microbial Biotechnology  2013;7(1):54-63.
Microbial electric systems (MESs) hold significant promise for the sustainable remediation of chlorinated solvents such as tetrachlorethene (perchloroethylene, PCE). Although the bio-electrochemical potential of some specific bacterial species such as Dehalcoccoides and Geobacteraceae have been exploited, this ability in other undefined microorganisms has not been extensively assessed. Hence, the focus of this study was to investigate indigenous and potentially bio-electrochemically active microorganisms in PCE-contaminated groundwater. Lab-scale MESs were fed with acetate and carbon electrode/PCE as electron donors and acceptors, respectively, under biostimulation (BS) and BS-bioaugmentation (BS-BA) regimes. Molecular analysis of the indigenous groundwater community identified mainly Spirochaetes, Firmicutes, Bacteroidetes, and γ and δ-Proteobacteria. Environmental scanning electron photomicrographs of the anode surfaces showed extensive indigenous microbial colonization under both regimes. This colonization and BS resulted in 100% dechlorination in both treatments with complete dechlorination occurring 4 weeks earlier in BS-BA samples and up to 11.5 μA of current being generated. The indigenous non-Dehalococcoides community was found to contribute significantly to electron transfer with ∼61% of the current generated due to their activities. This study therefore shows the potential of the indigenous non-Dehalococcoides bacterial community in bio-electrochemically reducing PCE that could prove to be a cost-effective and sustainable bioremediation practice.
PMCID: PMC3896933  PMID: 24119162
23.  Determining the Metabolic Footprints of Hydrocarbon Degradation Using Multivariate Analysis 
PLoS ONE  2013;8(11):e81910.
The functional dynamics of microbial communities are largely responsible for the clean-up of hydrocarbons in the environment. However, knowledge of the distinguishing functional genes, known as the metabolic footprint, present in hydrocarbon-impacted sites is still scarcely understood. Here, we conducted several multivariate analyses to characterise the metabolic footprints present in a variety of hydrocarbon-impacted and non-impacted sediments. Non-metric multi-dimensional scaling (NMDS) and canonical analysis of principal coordinates (CAP) showed a clear distinction between the two groups. A high relative abundance of genes associated with cofactors, virulence, phages and fatty acids were present in the non-impacted sediments, accounting for 45.7 % of the overall dissimilarity. In the hydrocarbon-impacted sites, a high relative abundance of genes associated with iron acquisition and metabolism, dormancy and sporulation, motility, metabolism of aromatic compounds and cell signalling were observed, accounting for 22.3 % of the overall dissimilarity. These results suggest a major shift in functionality has occurred with pathways essential to the degradation of hydrocarbons becoming overrepresented at the expense of other, less essential metabolisms.
PMCID: PMC3839897  PMID: 24282619
24.  Momentary Affect Surrounding Loss of Control and Overeating in Obese Adults With and Without Binge Eating Disorder 
Obesity (Silver Spring, Md.)  2011;20(6):10.1038/oby.2011.286.
Research suggests that loss of control (LOC) while eating (the sense that one cannot control what or how much one is eating) is a more salient feature of binge eating than the amount of food consumed. This study examined the unique contributions of LOC and episode size to negative affect surrounding eating episodes in binge eating disorder (BED) and obesity. Twenty-two obese adults with (n = 9) and without (n = 13) BED completed daily records of eating patterns and mood using ecological momentary assessment (EMA). Linear mixed modeling revealed that across groups, greater premeal self-reported LOC was associated with higher premeal negative affect independent of episode size. For individuals with BED, greater premeal self-reported LOC was associated with higher postmeal negative affect, regardless of the amount of food eaten, whereas for obese controls, the combination of LOC and consumption of large amounts of food was associated with lower postmeal negative affect. Results indicate that LOC, but not the quantity of food consumed, is associated with momentary distress related to aberrant eating in BED. Findings also highlight the need for further research investigating the emotional context surrounding aberrant eating in obese individuals without BED.
PMCID: PMC3816927  PMID: 21938073
25.  Adding Chemoprophylaxis to Sequential Compression May Not Reduce the Risk of Venous Thromboembolism in Bariatric Surgery Patients 
Anticoagulation, the use of sequential compression devices on lower extremities peri-operatively, and early ambulation are thought to reduce venous thromboembolism (VTE) postoperatively and are recommended to reduce VTE risk. However, the evidence upon which this recommendation is based is not particularly strong. We demonstrate that even a large, multi-center cohort with carefully collected prospective data is inadequate to provide sufficient evidence to support, or refute, this recommendation.
The Longitudinal Assessment of Bariatric Surgery (LABS) participants from 10 centers in the United States who underwent their first bariatric surgery between March, 2005 and December, 2007 comprise the study group. We examined the ability to address the question of whether anti-coagulation therapy, in addition to sequential compression, reduces the 30 day incidence of VTE or death sufficiently to recommend the use of prophylactic anticoagulation, a therapy that is not without risk.
Of 4416 patients, 396 (9.0%) received sequential compression alone, while the others also received anticoagulation therapy. The incidence of VTE within 30 days of surgery was small (0.25% among those receiving sequential compression alone, 0.47% when anticoagulation therapy was added), and the 30 days incidence of death was also small (0.25% vs. 0.34%, p = 0.76, for sequential compression alone vs. sequential compression plus anticoagulation therapy). Estimates of the number of cases required to address the question of whether there is a difference in outcome related to VTE chemoprophylaxis, or whether the outcome rates are equivalent, range from 13,680 to at least 35,760 patients, depending upon whether superiority or equivalence is being analyzed.
Sufficient evidence from a clinical trial study to determine whether prophylactic anticoagulation added to compression devices further prevents VTEs is not available and such a trial is likely to be impractical. The data presented are insufficient to make a final recommendation concerning prophylactic treatment to prevent VTE in the 30 days following bariatric surgery.
PMCID: PMC3498574  PMID: 22963819
bariatric surgery; thromboembolism; pulmonary emboli; chemoprophylaxis; deep vein thrombosis; sequential compression

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