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1.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38341719

ABSTRACT

We present an inversion method capable of robustly unfolding MeV x-ray spectra from filter stack spectrometer (FSS) data without requiring an a priori specification of a spectral shape or arbitrary termination of the algorithm. Our inversion method is based upon the perturbative minimization (PM) algorithm, which has previously been shown to be capable of unfolding x-ray transmission data, albeit for a limited regime in which the x-ray mass attenuation coefficient of the filter material increases monotonically with x-ray energy. Our inversion method improves upon the PM algorithm through regular smoothing of the candidate spectrum and by adding stochasticity to the search. With these additions, the inversion method does not require a physics model for an initial guess, fitting, or user-selected termination of the search. Instead, the only assumption made by the inversion method is that the x-ray spectrum should be near a smooth curve. Testing with synthetic data shows that the inversion method can successfully recover the primary large-scale features of MeV x-ray spectra, including the number of x-rays in energy bins of several-MeV widths to within 10%. Fine-scale features, however, are more difficult to recover accurately. Examples of unfolding experimental FSS data obtained at the Texas Petawatt Laser Facility and the OMEGA EP laser facility are also presented.

2.
Sci Total Environ ; 704: 135309, 2020 Feb 20.
Article in English | MEDLINE | ID: mdl-31896213

ABSTRACT

Sediment quality monitoring is widely used to quantify extent of river pollution, but requires knowledge of pre-disturbance conditions in the potentially altered landscape. This has long been identified as a critical aspect to develop for addressing concerns of river pollution in the Alberta Oil Sands Region. Here, we use analyses of sediment cores from eight floodplain lakes spanning a 67 river-km transect across the Athabasca Delta to define pre-1920 (pre-industrial) baseline concentrations for vanadium and five primary pollutants. We then evaluate if sediment metals concentrations have become enriched above baseline since onset of oil sands development and other industrial activities. Results demonstrate no enrichment of metals concentrations (except zinc at one lake) and absence of consistent temporal increases above pre-industrial baselines. Thus, natural processes continue to dominate metal deposition in floodplain lakes of the Athabasca Delta -- an important finding to inform stewardship decisions. The pre-1920 metals concentrations baselines offer a useful tool for ongoing sediment monitoring in aquatic ecosystems of the Athabasca Delta.

3.
J Aquat Anim Health ; 30(2): 119-129, 2018 06.
Article in English | MEDLINE | ID: mdl-29364539

ABSTRACT

Nondestructive, sublethal, and sensitive health monitoring tools are needed to assess the health of freshwater mussels (family Unionidae). Recent developments to standardize hemocyte characterization have assisted in the hematologic assessment of wild and captive freshwater mussels. In this study, preliminary baseline hematological reference ranges were established for wild mapleleaf mussels Quadrula quadrula (n = 14) and threeridge mussels Amblema plicata (n = 20) collected from the Muskingum River in Devola, Ohio. Mussels were collected from the wild, and hemolymph was sampled from each mussel in the field upon capture (baseline sample). They were then transported live to a propagation facility. Subsequent hemolymph samples were collected at 2 and 4 weeks and quarterly thereafter for 11 months following translocation. Hemocyte counts, hemocyte morphology, and hemolymph chemistry (Na+ , Cl- , Mg2+ , P3- , K+ , Ca2+ , glucose, alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase]) were measured from each sample on each sampling occasion. Hemocyte counts were consistently greater in Q. quadrula than in A. plicata following transfer to captivity. Baseline hemocyte morphology and hemolymph chemistry varied between species. This study provides a foundation of reference ranges for hemocyte characterization for Q. quadrula, and A. plicata and a preliminary understanding of how hemocyte character might be expected to change when wild mussels are translocated into captivity, and thus be a useful technique for monitoring the health of freshwater mussels.


Subject(s)
Hemocytes/cytology , Hemolymph/chemistry , Unionidae/physiology , Animals , Hemolymph/cytology , Ohio
4.
Vet Parasitol Reg Stud Reports ; 6: 31-34, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28529982

ABSTRACT

This study aimed to identify DNA attributed to Hammondia heydorni oocysts in the feces of wild canids in and around an Ohio wildlife conservation center. Two hundred and eighty-five wild canid fecal samples were analyzed using PCR with melting curve analysis to detect coccidian DNA. Coccidia-positive samples were further subjected to H. heydorni-specific and N. caninum-specific PCR assays. Samples positive by the H. heydorni-specific assay were additionally analyzed with a PCR assay to distinguish H. heydorni from Hammondia triffittae. Coccidian DNA was detected in 51 of the 285 (17.9%) wildlife samples. H. heydorni DNA was detected in three of the coccidia-positive wildlife samples (1.1%) and N. caninum was detected in none. Determining the presence of H. heydorni in wild canids will contribute to a greater understanding of the role these hosts play in the ecology of this parasite.

5.
Oncogene ; 34(21): 2711-20, 2015 May 21.
Article in English | MEDLINE | ID: mdl-25065592

ABSTRACT

Metabotropic glutamate 1 (mGlu) receptor has been proposed as a target for the treatment of metastatic melanoma. Studies have demonstrated that inhibiting the release of glutamate (the natural ligand of mGlu1 receptors), results in a decrease of melanoma tumor growth in mGlu1 receptor-expressing melanomas. Here we demonstrate that mGlu1 receptors, which have been previously characterized as oncogenes, also behave like dependence receptors by creating a dependence on glutamate for sustained cell viability. In the mGlu1 receptor-expressing melanoma cell lines SK-MEL-2 (SK2) and SK-MEL-5 (SK5), we show that glutamate is both necessary and sufficient to maintain cell viability, regardless of underlying genetic mutations. Addition of glutamate increased DNA synthesis, whereas removal of glutamate not only suppressed DNA synthesis but also promoted cell death in SK2 and SK5 melanoma cells. Using genetic and pharmacological inhibitors, we established that this effect of glutamate is mediated by the activation of mGlu1 receptors. The stimulatory potential of mGlu1 receptors was further confirmed in vivo in a melanoma cell xenograft model. In this model, subcutaneous injection of SK5 cells with short hairpin RNA-targeted downregulation of mGlu1 receptors resulted in a decrease in the rate of tumor growth relative to control. We also demonstrate for the first time that a selective mGlu1 receptor antagonist JNJ16259685 ((3,4-Dihydro-2H-pyrano[2,3-b]quinolin-7-yl)-(cis-4-methoxycyclohexyl)-methanone) slows SK2 and SK5 melanoma tumor growth in vivo. Taken together, these data suggest that pharmacological inhibition of mGlu1 receptors may be a novel approach for the treatment of metastatic melanoma.


Subject(s)
Cell Survival/physiology , Glutamic Acid/metabolism , Melanoma/metabolism , Receptors, Metabotropic Glutamate/metabolism , Animals , Cell Death/drug effects , Cell Death/physiology , Cell Line, Tumor , Cell Survival/drug effects , Humans , Melanoma/drug therapy , Mice , Mice, Inbred C57BL , Mice, Nude , Quinolines/pharmacology
6.
Zoonoses Public Health ; 62(6): 438-44, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25388917

ABSTRACT

The purpose of this study was to investigate the occurrence, antimicrobial resistance patterns, phenotypic and genotypic relatedness of Salmonella enterica recovered from captive wildlife host species and in the environment in Ohio, USA. A total of 319 samples including faecal (n = 225), feed (n = 38) and environmental (n = 56) were collected from 32 different wild and exotic animal species in captivity and their environment in Ohio. Salmonellae were isolated using conventional culture methods and tested for antimicrobial susceptibility with the Kirby-Bauer disc diffusion method. Salmonella isolates were serotyped, and genotyping was performed using the pulsed-field gel electrophoresis (PFGE). Salmonella was detected in 56 of 225 (24.9%) faecal samples; six of 56 (10.7%) environmental samples and six of 38 (15.8%) feed samples. Salmonella was more commonly isolated in faecal samples from giraffes (78.2%; 36/46), cranes (75%; 3/4) and raccoons (75%; 3/4). Salmonella enterica serotypes of known public health significance including S. Typhimurium (64.3%), S. Newport (32.1%) and S. Heidelberg (5.3%) were identified. While the majority of the Salmonella isolates were pan-susceptible (88.2%; 60 of 68), multidrug-resistant strains including penta-resistant type, AmStTeKmGm (8.8%; six of 68) were detected. Genotypic diversity was found among S. Typhimurium isolates. The identification of clonally related Salmonella isolates from environment and faeces suggests that indirect transmission of Salmonella among hosts via environmental contamination is an important concern to workers, visitors and other wildlife. Results of this study show the diversity of Salmonella serovars and public health implications of human exposure from wildlife reservoirs.


Subject(s)
Animals, Exotic , Animals, Wild/microbiology , Salmonella Infections, Animal/epidemiology , Salmonella enterica/isolation & purification , Animal Feed/microbiology , Animals , Animals, Zoo , Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Environment , Environmental Microbiology , Feces/microbiology , Genotype , Ohio/epidemiology , Phenotype , Salmonella enterica/classification , Salmonella enterica/genetics
7.
Nurs Leadersh (Tor Ont) ; 27(2): 56-67, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25073057

ABSTRACT

Nurse migration is of global concern for every country, and study of migration can provide critical information for managers concerned with nurse recruitment and retention. This mixed-methods research examined factors influencing registered nurses' (RNs') decisions to work in their home country, Canada, or to commute daily to a nursing position in the United States. Measures included nurses' feelings about their work environment conditions, work status congruence (the goodness of fit between employer expectations and their own regarding hours and times worked), professional development opportunities, and their perceptions of organizational support and autonomy (freedom and independence) in the workplace. All work environment variables were significantly higher for nurses working in Michigan. Qualitative results supported these survey findings, providing additional information about nurses' satisfaction. Nurses in our sample were more satisfied with all the work environment factors examined, even when stress from commuting out of country was experienced. The environmental issues examined in this study should be considered by nurse managers concerned with recruitment and retention of nurses.


Subject(s)
Decision Making , Emigration and Immigration/trends , Nurse Administrators , Personnel Selection/trends , Personnel Turnover/trends , Transportation , Adult , Attitude of Health Personnel , Female , Humans , Job Satisfaction , Male , Michigan , Middle Aged , Ontario , Social Environment , Surveys and Questionnaires , Workload , Workplace
8.
J Anim Physiol Anim Nutr (Berl) ; 97(3): 566-76, 2013 Jun.
Article in English | MEDLINE | ID: mdl-22497558

ABSTRACT

Urolith formation has been documented in giraffes and goats. As research in giraffes poses logistical challenges, 16 buck goats were used as a model. The impact of two commercially available, pelleted feeds used for giraffes, ADF-16 and Wild Herbivore (WH), as well as the impact of alfalfa hay and pellet proportions (20% hay:80% pellets, 80P or 80% hay:20% pellet, 20P) on the formation of urolithogenic precursors in goat urine was accomplished in a 2 × 2 factorial balance study. Complete diets contained 0.60, 0.32, 0.35 and 0.26% phosphorus (P) with calcium:P ratios of 1.60, 4.16, 3.06 and 5.23, for 80P-ADF-16, 20P-ADF-16, 80P-WH and 20P-WH respectively. Total faeces and urine were collected over two 5-day periods to assess N and mineral balance. Fresh urine samples were collected and evaluated microscopically for urolithic crystal content. Urinary nitrogen (N) was lower and N retention was higher in goats fed 80P diets (p < 0.05). Intake of P was greatest for goats fed 80P-ADF-16; however, urinary P excretion and P retention were not affected by treatment. Crystal scores were higher in animals receiving 80P diets (p = 0.08), with crystals being composed predominantly of calcium phosphate. Urine pH was alkaline (>8) for all treatments. Urinary P concentration, a risk factor for urolithiasis, was highest (p ≤ 0.06) in the 80P-ADF-16 treatment (0.38 vs. 0.01, 0.02 and 0.04 mg/dl for 20P-ADF-16, 80P-WH and 20P-WH respectively), reflecting its highest dietary P level. Further investigation is recommended to determine the long-term effects of these diets on urolithogenic compound formation.


Subject(s)
Animal Feed/analysis , Antelopes , Creatinine/urine , Food Handling , Goats/physiology , Animal Husbandry/methods , Animals , Animals, Wild , Calcium/urine , Calcium, Dietary/analysis , Calcium, Dietary/metabolism , Digestion , Dose-Response Relationship, Drug , Nutritional Requirements , Nutritive Value , Phosphorus/urine , Phosphorus, Dietary/analysis , Phosphorus, Dietary/metabolism , Urolithiasis/prevention & control , Urolithiasis/veterinary
9.
Eat Weight Disord ; 17(3): e200-2, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23086256

ABSTRACT

PURPOSE: The purpose of this study was to investigate gender differences in binge eating and associated behavioral correlates in college students. METHODS: A webbased survey was conducted with 2073 students (mean age 19.8 yr; range 18-23 yr). Multiple logistic regression was used to calculate odds ratios and 95% confidence intervals for the factors associated with binge eating. RESULTS: Twenty-nine percent of students reported recent bingeing. Factors associated with binge eating included being female, having a higher body mass index, current tobacco use, and exercising to lose weight. Women were more likely to binge eat (73.8%; χ(2)=32.3; p≤0.001), report loss of control (45%; χ(2)=16.3; p≤0.001), self induced vomiting (20.7%; χ(2)=15.9; p≤0.001), and laxative use (6.7%; χ(2)=8.93; p≤0.001). CONCLUSIONS: Results generated from this study suggest that gender-disparate behaviors are potential targets for future tailored interventions.


Subject(s)
Bulimia/epidemiology , Feeding Behavior , Students/statistics & numerical data , Universities , Adolescent , Body Mass Index , Cross-Sectional Studies , Exercise , Female , Humans , Male , Multivariate Analysis , Regression Analysis , Risk Factors , Sex Factors , Smoking/epidemiology , Surveys and Questionnaires , Young Adult
10.
Phys Rev Lett ; 106(4): 041803, 2011 Jan 28.
Article in English | MEDLINE | ID: mdl-21405320

ABSTRACT

We report a measurement of the positive muon lifetime to a precision of 1.0 ppm; it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2×10(12) decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give τ(µ(+)) (MuLan)=2 196 980.3(2.2) ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G(F) (MuLan)=1.166 378 8(7)×10(-5) GeV(-2) (0.6 ppm). It is also used to extract the µ(-)p singlet capture rate, which determines the proton's weak induced pseudoscalar coupling g(P).

11.
Yearb Med Inform ; : 13-20, 2010.
Article in English | MEDLINE | ID: mdl-20938564

ABSTRACT

OBJECTIVES: The overall objective of this project was to investigate ways to strengthen the OpenMRS community by (i) developing capacity and implementing a network focusing specifically on the needs of OpenMRS implementers, (ii) strengthening community-driven aspects of OpenMRS and providing a dedicated forum for implementation-specific issues, and; (iii) providing regional support for OpenMRS implementations as well as mentorship and training. METHODS: The methods used included (i) face-to-face networking using meetings and workshops; (ii) online collaboration tools, peer support and mentorship programmes; (iii) capacity and community development programmes, and; (iv) community outreach programmes. RESULTS: The community-driven approach, combined with a few simple interventions, has been a key factor in the growth and success of the OpenMRS Implementers Network. It has contributed to implementations in at least twenty-three different countries using basic online tools; and provided mentorship and peer support through an annual meeting, workshops and an internship program. The OpenMRS Implementers Network has formed collaborations with several other open source networks and is evolving regional OpenMRS Centres of Excellence to provide localized support for OpenMRS development and implementation. These initiatives are increasing the range of functionality and sustainability of open source software in the health domain, resulting in improved adoption and enterprise-readiness. CONCLUSIONS: Social organization and capacity development activities are important in growing a successful community-driven open source software model.


Subject(s)
Capacity Building , Medical Records Systems, Computerized/organization & administration , Software , Humans , Internet , Ownership
12.
Theriogenology ; 74(9): 1701-6, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20615535

ABSTRACT

The objective was to determine if seminal alkaline phosphatase (ALP) can serve as an indicator of true ejaculation in the rhinoceros. Concentrations of ALP activity were determined in seminal fractions collected from African black rhinos (Diceros bicornis), an African white rhino (Ceratotherium simum), and an Indian rhino (Rhinoceros unicornis) during electroejaculation. In addition, seminal fractions collected during penile massage of a Sumatran rhino (Dicerorhinus sumatrensis) were assessed. Correlations between ALP activity and sperm concentration, fraction pH, and fraction osmolality were evaluated in the Indian rhino and black rhino. Concentrations of ALP activity in rhino ejaculate fractions ranged from < 5 to 11,780 U/L and were positively correlated (P < 0.05) with sperm concentration for both Indian rhino (r = 0.995) and black rhino (r = 0.697), but did not exhibit a strong correlation with either pH or osmolality (P > 0.05). Data were insufficient for establishing meaningful correlation coefficients in the Sumatran rhino and white rhino, but preliminary results were in accordance with findings in the Indian rhino and black rhino. We concluded that ALP was present in rhinoceros semen, likely originated from the epididymides and/or testes, and could serve as a useful tool for assessing the production of ejaculatory versus pre-ejaculatory fluid in the rhinoceros.


Subject(s)
Alkaline Phosphatase/analysis , Ejaculation , Perissodactyla/metabolism , Semen/enzymology , Animals , Hydrogen-Ion Concentration , Male , Osmolar Concentration , Sperm Count/veterinary
13.
Int J Clin Pract ; 63(9): 1285-300, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19691612

ABSTRACT

OBJECTIVE: To review how bariatric surgery in obese patients may effectively treat adiposopathy (pathogenic adipose tissue or 'sick fat'), and to provide clinicians a rationale as to why bariatric surgery is a potential treatment option for overweight patients with type 2 diabetes, hypertension, and dyslipidaemia. METHODS: A group of clinicians, researchers, and surgeons, all with a background in treating obesity and the adverse metabolic consequences of excessive body fat, reviewed the medical literature regarding the improvement in metabolic disease with bariatric surgery. RESULTS: Bariatric surgery improves metabolic disease through multiple, likely interrelated mechanisms including: (i) initial acute fasting and diminished caloric intake inherent with many gastrointestinal surgical procedures; (ii) favourable alterations in gastrointestinal endocrine and immune responses, especially with bariatric surgeries that reroute nutrient gastrointestinal delivery such as gastric bypass procedures; and (iii) a decrease in adipose tissue mass. Regarding adipose tissue mass, during positive caloric balance, impaired adipogenesis (resulting in limitations in adipocyte number or size) and visceral adiposity are anatomic manifestations of pathogenic adipose tissue (adiposopathy). This may cause adverse adipose tissue endocrine and immune responses that lead to metabolic disease. A decrease in adipocyte size and decrease in visceral adiposity, as often occurs with bariatric surgery, may effectively improve adiposopathy, and thus effectively treat metabolic disease. It is the relationship between bariatric surgery and its effects upon pathogenic adipose tissue that is the focus of this discussion. CONCLUSIONS: In selective obese patients with metabolic disease who are refractory to medical management, adiposopathy is a surgical disease.


Subject(s)
Adiposity , Bariatric Surgery/methods , Obesity/surgery , Cost-Benefit Analysis , Humans , Life Style , Metabolic Diseases/therapy , Obesity/pathology , Patient Education as Topic , Practice Guidelines as Topic , Risk Factors , Treatment Outcome , Weight Loss
14.
Theriogenology ; 71(1): 149-65, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-18986694

ABSTRACT

Artificial insemination technology has revolutionized the domestic cattle breeding industry and allowed for the dissemination of valuable genetics worldwide. This technology has been adapted for use in many other taxa for the conservation of threatened and endangered species, but its use for the genetic management of small populations of deer, antelope and other non-domestic bovids has met numerous challenges and limited success. In practice, adaptation of domestic bovine AI protocols to other artiodactylids for genetic management has been limited by: (1) a lack of understanding of species-specific reproductive characteristics; (2) the inability to minimize handling stress; (3) pregnancy losses; and (4) regulatory challenges in semen importation. To date, AI protocols have been developed for seven species of cervid and 14 species of non-domestic bovids; recent developments in this technology has allowed greater use of AI for dissemination of genetics in farmed deer species. However, despite decades of research in the use of assisted reproduction for the conservation of antelope and other non-domestic bovids, even this simplest technique has not been used repeatedly for genetic management.


Subject(s)
Artiodactyla , Insemination, Artificial/veterinary , Animals , Animals, Wild , Artiodactyla/genetics , Artiodactyla/physiology
15.
Vet Pathol ; 46(1): 120-3, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19112125

ABSTRACT

A 7-year-old captive female prothonotary warbler (Protonotaria citrea) died following chronic feather and weight loss. At necropsy, the right eye had a 2 x 2 x 1 mm corneal plaque of inspissated yellow-tan material and edema of the lower eyelid. Microscopically, both eyes exhibited diffuse, severe pyogranulomatous endophthalmitis with retinal necrosis and detachment. Numerous intralesional branching, gram-positive, beaded, filamentous bacteria formed a thick mat attached to the retinal pigmented epithelium and extending into the pecten. Bacteria were strongly acid-fast positive by Fite's stain but only occasionally acid-fast positive by Ziehl-Neelsen staining, a characteristic consistent with a Nocardia spp. Infected regions demonstrated positive in situ hybridization reactivity with a probe complementary to the 16S rRNA gene of Nocardia spp. There was no evidence of primary bacterial infection in the other organs examined.


Subject(s)
Bird Diseases/microbiology , Bird Diseases/pathology , Endophthalmitis/veterinary , Eye/pathology , Nocardia Infections/veterinary , Nocardia/genetics , Songbirds , Animals , Endophthalmitis/microbiology , Endophthalmitis/pathology , Fatal Outcome , Female , In Situ Hybridization , Nocardia Infections/pathology , RNA, Ribosomal, 16S/genetics
16.
Diabetologia ; 51(10): 1901-11, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18704364

ABSTRACT

AIMS/HYPOTHESIS: Bariatric surgery is an effective treatment for severe obesity, as in addition to dramatic weight loss, co-morbidities such as type 2 diabetes are frequently resolved. Although altered gastrointestinal peptide hormone secretion and its relationship with post-surgical improvements in insulin sensitivity has been studied, much less is known about long-term changes in pancreatic and adipose tissue-derived hormones. Our objective was to conduct a comprehensive longitudinal investigation of the endocrine changes following Roux-en-Y gastric bypass surgery (RYGBP), focusing on pancreatic and adipocyte hormones and systemic markers of inflammation. METHODS: Nineteen severely obese women (BMI 45.6 +/- 1.6 kg/m(2)) were studied prior to RYGBP, and at 1, 3, 6, and 12 months after RYGBP. Body composition was assessed before surgery and at 1 and 12 months. RESULTS: Pre-surgical adiposity was correlated with circulating adipocyte hormones (leptin, visfatin) and inflammatory molecules (IL-6, high sensitivity C-reactive protein [hsCRP], monocyte chemoattractant protein-1). As expected, RYGBP reduced fat mass and fasting insulin and glucose concentrations. In addition, reductions of fasting pancreatic polypeptide (PP) and glucagon concentrations were observed at 1 and 3 months, respectively. In the 12 months following RYGBP, concentrations of most adipocyte hormones (leptin, acylation-stimulating hormone and visfatin, but not retinol-binding hormone-4) and inflammatory molecules (IL-6, hsCRP and soluble intracellular adhesion molecule-1) were significantly reduced. Reductions of insulin resistance (measured by homeostasis model assessment of insulin resistance) were independently associated with changes of glucagon, visfatin and PP. Pre-surgical HMW adiponectin concentrations independently predicted losses of body weight and fat mass. CONCLUSIONS/INTERPRETATION: These results suggest that pancreatic and adipocyte hormones may contribute to the long-term resolution of insulin resistance after RYGBP.


Subject(s)
Adipocytes/metabolism , Gastric Bypass/methods , Obesity, Morbid/surgery , Pancreas/metabolism , Adult , C-Reactive Protein/metabolism , Chemokine CCL2/metabolism , Female , Glucagon/metabolism , Glucose/metabolism , Humans , Interleukin-6/metabolism , Leptin/metabolism , Longitudinal Studies , Obesity, Morbid/metabolism , Obesity, Morbid/pathology , Retinol-Binding Proteins, Plasma/metabolism , Time Factors
17.
Int J Obes (Lond) ; 32(9): 1395-406, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18645576

ABSTRACT

CONTEXT: Gastric bypass surgery is the most commonly performed bariatric surgical procedure in the United States. Variable weight loss following this relatively standardized intervention has been reported. To date, a method for reliable profiling of patients who will successfully sustain weight loss for the long term has not been established. In addition, the mechanisms of action in accomplishing major weight loss as well as the explanation for the variable weight loss have not been established. OBJECTIVE: To examine whether gene expression in perioperative omental adipose is associated with gastric bypass-induced weight loss. DESIGN: Cross-sectional study of gene expression in perisurgical omental adipose tissues taken/available at the time of operation and total excess weight loss (EWL). SUBJECTS: Fifteen overweight individuals who underwent Roux-en-Y gastric bypass (RYGB) surgery at the University of California Davis Medical Center (BMI: 40.6-72.8 kg/m(2)). MEASUREMENTS: Body weight before and following weight stabilization 18-42 months after surgery. Perioperative omental adipose RNA isolated from 15 subjects was hybridized to Affymetrix HG-U133A chips for 22,283 transcript expression measurements. RESULTS: Downstream analysis identified a set of genes whose expression was significantly correlated with RYGB-induced weight loss. The significant individual genes include acyl-coenzyme A oxidase 1 (ACOX1), phosphodiesterase 3A cGMP-inhibited (PDE3A) and protein kinase, AMP-activated, beta 1 non-catalytic subunit (PRKAB1). Specifically, ACOX1 plays a role in fatty acid metabolism. PDE3A is involved in purine metabolism and hormone-stimulated lipolysis. PRKAB1 is involved in adipocytokine signaling pathway. Gene network analysis revealed that pathways for glycerolipid metabolism, breast cancer and apoptosis were significantly correlated with long-term weight loss. CONCLUSION: This study demonstrates that RNA expression profiles from perioperative adipose tissue are associated with weight loss outcome following RYGB surgery. Our data suggest that EWL could be predicted from preoperative samples, which would allow for informed decisions about whether or not to proceed to surgery.


Subject(s)
Abdominal Fat/metabolism , Gastric Bypass , Obesity, Morbid/surgery , Omentum/metabolism , Weight Loss/genetics , Adolescent , Adult , Anthropometry/methods , Biomarkers/metabolism , Body Weight , Cross-Sectional Studies , Feasibility Studies , Gene Expression Profiling/methods , Gene Regulatory Networks , Humans , Metabolic Networks and Pathways/genetics , Middle Aged , Obesity, Morbid/genetics , Obesity, Morbid/physiopathology , Prognosis , Protein Array Analysis/methods , RNA, Messenger/genetics , Signal Transduction/genetics , Treatment Outcome , Young Adult
18.
Psychol Med ; 38(10): 1435-42, 2008 Oct.
Article in English | MEDLINE | ID: mdl-17825120

ABSTRACT

BACKGROUND: Recent studies suggest that purging disorder (PD) may be a common eating disorder that is associated with clinically significant levels of distress and high levels of psychiatric co-morbidity. However, no study has established evidence of disorder-related impairment or whether distress is specifically related to PD rather than to co-morbid disorders. METHOD: Three groups of normal-weight women [non-eating disorder controls (n=38), with PD (n=24), and with bulimia nervosa (BN)-purging subtype (n=57)] completed structured clinical interviews and self-report assessments. RESULTS: Both PD and BN were associated with significant co-morbidity and elevations on indicators of distress and impairment compared to controls. Compared to BN, PD was associated with lower rates of current and lifetime mood disorders but higher rates of current anxiety disorders. Elevated distress and impairment were maintained in PD and BN after controlling for Axis I and Axis II disorders. CONCLUSIONS: PD is associated with elevated distress and impairment and should be considered for inclusion as a provisional disorder in nosological schemes such as the Diagnostic and Statistical Manual to facilitate much-needed research on this clinically significant syndrome.


Subject(s)
Bulimia Nervosa/epidemiology , Bulimia Nervosa/psychology , Depression/epidemiology , Depression/psychology , Adult , Comorbidity , Diagnostic and Statistical Manual of Mental Disorders , Female , Humans , Prevalence , Severity of Illness Index , Social Adjustment , Surveys and Questionnaires
19.
Dis Esophagus ; 20(3): 269-73, 2007.
Article in English | MEDLINE | ID: mdl-17509126

ABSTRACT

The long-term effects of gastric banding on esophageal function are not well described. This report describes a 28-year-old woman who developed signs and symptoms of abnormal esophageal motility and lower esophageal sphincter hypotension after gastric banding for morbid obesity. The current literature addressing the effects of gastric banding on esophageal function in light of this case report is discussed.


Subject(s)
Esophageal Motility Disorders/etiology , Gastroplasty/adverse effects , Obesity, Morbid/surgery , Adult , Female , Humans
20.
Surg Endosc ; 21(9): 1593-9, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17294310

ABSTRACT

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a major cause of liver disease in morbidly obese patients. Clinical predictors of NASH remain elusive, as do molecular mechanisms of pathogenesis. METHODS: A series of 35 morbidly obese patients undergoing bariatric surgery had a liver biopsy performed for standard histologic analysis. In addition, RNA was obtained from liver tissue and analyzed for leptin receptor gene expression. Regression analysis was used to correlate clinical variables, including serum leptin levels and hepatic leptin receptor gene expression, with the presence of histologically confirmed NASH. RESULTS: Of the 35 subjects enrolled, 29% had steatosis only, 60% had NASH, and 11% had normal liver histology. Among the clinical variables studied, only diabetes mellitus was an independent predictor of NASH. There was a trend toward lower levels of mRNA encoding the long form of the leptin receptor in hepatic tissue from patients with NASH compared to those with steatosis only. CONCLUSIONS: Diabetes mellitus is associated with an increased risk of NASH in obese patients. Downregulation of hepatic leptin receptor may play a role in the pathogenesis of NASH.


Subject(s)
Bariatric Surgery , Fatty Liver/diagnosis , Leptin/blood , Liver/metabolism , Obesity, Morbid/complications , Receptors, Cell Surface/metabolism , Adult , Biomarkers/blood , Fatty Liver/etiology , Female , Humans , Male , Middle Aged , Obesity, Morbid/metabolism , Obesity, Morbid/surgery , Receptors, Cell Surface/genetics , Receptors, Leptin , Risk Factors , Transcription, Genetic
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