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Obesity is a primary risk factor for knee osteoarthritis (OA), which is the most prevalent chronic joint condition and the leading cause of disability in the US, especially among people over 65 years. The objective of this study was to determine if an intensive 6-month weight loss program (10-12% of initial body weight) altered concentrations of five serum inflammatory biomarkers (IL-6, TNFα, TNF soluble receptor 1 (TNFR1), TNFR2, and C-reactive protein) and to assess whether improvements in physical function resulting from weight loss are related to decreases in these inflammatory biomarkers. Seventy elderly, overweight individuals were randomized to either a weight loss (WL) or weight stable (WS) group. At baseline, higher IL-6 and TNFR1 concentrations were related to increased stair climb time (p≤0.03); increased time indicates poorer function. In response to the interventions, serum concentrations of TNFR1 decreased in WL compared to WS (-5.2% vs. +10.2%, p≤0.05), but there were no changes in other inflammatory biomarkers. Decreases in self-reported stiffness and pain were related to decreases in IL-6 and TNFR1 (p≤0.04). In summary, pain, stiffness, and physical function are associated with circulating IL-6 and TNFR1 in overweight adults with knee OA. These findings suggest that a low level of chronic inflammation may play an important role in modulating pain and function in knee OA. [ABSTRACT FROM AUTHOR]

Objective: The study objective was to determine whether the clinical response of older adults with knee osteoarthritis and overweight or obesity to 18 months of diet and exercise (D + E) or attention control (C) interventions differed between participants from rural versus urban communities., Methods: Participants were 823 older adults (mean age, 64.6 years; 77% women) with knee osteoarthritis and overweight or obesity who resided in rural (n = 410) and urban (n = 413) counties in North Carolina. All were enrolled in the Weight Loss and Exercise for Communities with Arthritis in North Carolina clinical trial that randomly assigned participants to either 18 months of D + E or C interventions. General linear models were used to examine differences in clinical outcomes between rural and urban groups after adjusting for covariates., Results: The rural group had significant differences (P < 0.05) at baseline in clinical outcomes, education, comorbidities, medication use, and income compared with the urban dwellers. After adjusting for baseline differences, the group (rural or urban) by treatment (D + E or C) interactions for Western Ontario McMasters Universities Osteoarthritis Index (WOMAC) pain (rural: D + E - C = -0.63, 95% confidence interval [CI] -1.31 to 0.06; urban: D + E - C= -0.29, 95% CI -0.99 to 0.41; P = 0.50) and WOMAC function (rural: D + E - C = -4.60, 95% CI -6.89 to -2.31; urban: D + E - C = -1.38, 95% CI -3.73 to 0.94; P = 0.054) indicated that the groups responded similarly to the interventions., Conclusion: Among participants with knee osteoarthritis and overweight or obesity, D + E compared to C led to similar pain outcomes in rural and urban dwellers that favored D + E. The possibility that there may be greater differential efficacy in functional outcomes among rural participants needs further study., (© 2024 The Author(s). Arthritis Care & Research published by Wiley Periodicals LLC on behalf of American College of Rheumatology.)

The Enhancing Undergraduate Education and Research in Aging to Eliminate Health Disparities (ENGAGED) program takes advantage of the broad, multidisciplinary research established in the area of aging at Wake Forest University School of Medicine and its partner institutions, Wake Forest University and Winston-Salem State University. The ENGAGED program is designed to provide undergraduate students who are underrepresented in the biomedical sciences an opportunity to participate in educational and research training in aging and health disparities. Funded since August 2019, ENGAGED has provided 73 academic year internships and 46 summer internships, with another 8 internships starting in Fall 2023. A total of 61 students (67% female, 64% African American, 21% Hispanic) have participated in the ENGAGED program, reflecting the fact that 49% participate in more than one session or program offering. To date, 38 of the ENGAGED trainees have graduated (100% with a science, technology, engineering, or math degree), 84% of whom are working or pursuing advanced degrees in the biomedical sciences. Given the unique strengths, existing infrastructure, and long-standing collaborations among the partner institutions, the ENGAGED program is helping advance diversity in aging and health disparities research by creating a pipeline for well-trained underrepresented students interested in biomedical research careers.

Background: Osteoarthritis (OA), the leading cause of disability among adults, has no cure and is associated with significant comorbidities. The premise of this randomized clinical trial is that, in a population at risk, a 48-month program of dietary weight loss and exercise will result in less incident structural knee OA compared to control., Methods/design: The Osteoarthritis Prevention Study (TOPS) is a Phase III, assessor-blinded, 48-month, parallel 2 arm, multicenter randomized clinical trial designed to reduce the incidence of structural knee OA. The study objective is to assess the effects of a dietary weight loss, exercise, and weight-loss maintenance program in preventing the development of structural knee OA in females at risk for the disease. TOPS will recruit 1230 ambulatory, community dwelling females with obesity (Body Mass Index (BMI) ​≥ ​30 ​kg/m 2 ) and aged ≥50 years with no radiographic (Kellgren-Lawrence grade ≤1) and no magnetic resonance imaging (MRI) evidence of OA in the eligible knee, with no or infrequent knee pain. Incident structural knee OA (defined as tibiofemoral and/or patellofemoral OA on MRI) assessed at 48-months from intervention initiation using the MRI Osteoarthritis Knee Score (MOAKS) is the primary outcome. Secondary outcomes include knee pain, 6-min walk distance, health-related quality of life, knee joint loading during gait, inflammatory biomarkers, and self-efficacy. Cost effectiveness and budgetary impact analyses will determine the value and affordability of this intervention., Discussion: This study will assess the efficacy and cost effectiveness of a dietary weight loss, exercise, and weight-loss maintenance program designed to reduce incident knee OA., Trial Registration: ClinicalTrials.gov Identifier: NCT05946044., Competing Interests: Dr. Katz and Dr. Losina received research grant funding from Samumed and Flexion Therapeutics. Elena Losina has also received research funding from Pfizer. Dr. Hunter received research funding from Pfizer, Novartis, Lilly, Merck Serono, TLC Biopharmaceuticals and Kolon. Dr. Guermazi is a consultant for Pfizer, Novartis, TissueGene, Coval, Medipost, ICM and TrialSpark, and is a shareholder in Boston Imaging Core Lab. Kurt Spindler is a consultant for the National Football League and Novopedics, Inc. Dr.Cook receives research support from AO Trauma, Arthrex, Inc., Collagen Matrix Inc., DePuy, A Johnson & Johnson Company, Musculoskeletal Transplant Foundation, Orthopaedic Trauma Association, Purina, Regenosine, SITES Medical, Thieme, and Trupanion., (© 2023 The Author(s).)

Nitrate rich beetroot juice (BRJ) can enhance nitric oxide signaling, leading to improved physical function in healthy and diseased populations, but its safety and biologic efficacy have not been evaluated in a critically ill population. We randomized 22 previously functional acute respiratory failure patients to either BRJ or placebo daily until day 14 or discharge. We measured blood nitrate and nitrite levels and quantified strength and physical function at intensive care unit (ICU) and hospital discharge. Participants were predominantly male (54%), aged 68.5 years with an APACHE III score of 62. BRJ increased plasma nitrate (mean 219.2 μM increase, p = 0.002) and nitrite levels (mean 0.144 μM increase, p = 0.02). We identified no adverse events. The unadjusted and adjusted effect sizes of the intervention on the short physical performance battery were small (d = 0.12 and d = 0.17, respectively). In this pilot trial, administration of BRJ was feasible and safe, increased blood nitrate and nitrate levels, but had a small effect on physical function. Future studies could evaluate the clinical efficacy of BRJ as a therapy to improve physical function in survivors of critical illness., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Serial changes in dietary intake, including specific food groups and nutrients during the first year following Roux-en-Y gastric bypass (RYGB) are of interest due to surgically induced alterations in meal size, food intolerances present after surgery, and potential nutrient deficiencies. To help improve the nutritional health of surgical patients, this study's purpose was to examine changes in macro- and micronutrients, food groups, and selected foods during 12 months of follow-up in post-RYGB individuals., Methods: RYGB patients (n = 17) completed 4-day food records at baseline (prior to surgery) and then at 3 weeks, 3 months, 6 months, and 12 months after surgery. Mean daily intake was determined at each time for energy intake, macro- and micronutrients, food groups, and selected foods in targeted food groups., Results: A dramatic decrease in mean (± SEM) daily energy intake occurred--2,150 ± 165 kcal at baseline vs. 649 ± 40 kcal at 3 weeks; energy intake continually increased to a high of 1,307 ± 129 kcal by 12 months. More than 50 % of patients had low intake of vitamins D, E, C, folate, and calcium, magnesium, and potassium at 12 months. Servings from vegetables, grains, fats, and sweetened beverages were lower, whereas, meats, dairy, fruits, and sweets showed only small, transient changes following surgery., Conclusions: The reduction in energy intake following RYGB is from selected food groups and not solely a reduction in portion sizes across the diet. The lower intake of micronutrients indicates potential risk for deficiencies unless supplements are used. These findings can help in the clinical management of surgical patients to improve nutritional health.

Importance: Knee osteoarthritis (OA), a common cause of chronic pain and disability, has biomechanical and inflammatory origins and is exacerbated by obesity., Objective: To determine whether a ≥10% reduction in body weight induced by diet, with or without exercise, would improve mechanistic and clinical outcomes more than exercise alone., Design, Setting, and Participants: Single-blind, 18-month, randomized clinical trial at Wake Forest University between July 2006 and April 2011. The diet and exercise interventions were center-based with options for the exercise groups to transition to a home-based program. Participants were 454 overweight and obese older community-dwelling adults (age ≥55 years with body mass index of 27-41) with pain and radiographic knee OA., Interventions: Intensive diet-induced weight loss plus exercise, intensive diet-induced weight loss, or exercise., Main Outcomes and Measures: Mechanistic primary outcomes: knee joint compressive force and plasma IL-6 levels; secondary clinical outcomes: self-reported pain (range, 0-20), function (range, 0-68), mobility, and health-related quality of life (range, 0-100)., Results: Three hundred ninety-nine participants (88%) completed the study. Mean weight loss for diet + exercise participants was 10.6 kg (11.4%); for the diet group, 8.9 kg (9.5%); and for the exercise group, 1.8 kg (2.0%). After 18 months, knee compressive forces were lower in diet participants (mean, 2487 N; 95% CI, 2393 to 2581) compared with exercise participants (2687 N; 95% CI, 2590 to 2784, pairwise difference [Δ](exercise vs diet )= 200 N; 95% CI, 55 to 345; P = .007). Concentrations of IL-6 were lower in diet + exercise (2.7 pg/mL; 95% CI, 2.5 to 3.0) and diet participants (2.7 pg/mL; 95% CI, 2.4 to 3.0) compared with exercise participants (3.1 pg/mL; 95% CI, 2.9 to 3.4; Δ(exercise vs diet + exercise) = 0.39 pg/mL; 95% CI, -0.03 to 0.81; P = .007; Δ(exercise vs diet )= 0.43 pg/mL; 95% CI, 0.01 to 0.85, P = .006). The diet + exercise group had less pain (3.6; 95% CI, 3.2 to 4.1) and better function (14.1; 95% CI, 12.6 to 15.6) than both the diet group (4.8; 95% CI, 4.3 to 5.2) and exercise group (4.7; 95% CI, 4.2 to 5.1, Δ(exercise vs diet + exercise) = 1.02; 95% CI, 0.33 to 1.71; P(pain) = .004; 18.4; 95% CI, 16.9 to 19.9; Δ(exercise vs diet + exercise), 4.29; 95% CI, 2.07 to 6.50; P(function )< .001). The diet + exercise group (44.7; 95% CI, 43.4 to 46.0) also had better physical health-related quality of life scores than the exercise group (41.9; 95% CI, 40.5 to 43.2; Δ(exercise vs diet + exercise) = -2.81; 95% CI, -4.76 to -0.86; P = .005)., Conclusions and Relevance: Among overweight and obese adults with knee OA, after 18 months, participants in the diet + exercise and diet groups had more weight loss and greater reductions in IL-6 levels than those in the exercise group; those in the diet group had greater reductions in knee compressive force than those in the exercise group., Trial Registration: clinicaltrials.gov Identifier: NCT00381290.

Background: The prevalence of obesity in older adults is increasing but concerns exist about the effect of weight loss on muscle function. Demonstrating that muscle strength and power are not adversely affected during "intentional" weight loss in older adults is important given the wide-ranging negative health effects of excess adiposity., Methods: Participants (N = 88; age = 70.6 ± 3.6 years; body mass index = 32.8 ± 4.5 kg/m(2)) were randomly assigned to one of four intervention groups: pioglitazone or placebo and resistance training (RT) or no RT, while undergoing intentional weight loss via a hypocaloric diet. Outcomes were leg press power and isometric knee extensor strength. Analysis of covariance, controlling for baseline values, compared follow-up means of power and strength according to randomized groups., Results: Participants lost an average of 6.6% of initial body mass, and significant declines were observed in fat mass, lean body mass, and appendicular lean body mass. Compared with women not randomized to RT, women randomized to RT had significant improvements in leg press power (p < .001) but not in knee extensor strength (p = 0.12). No significant differences between groups in change in power or strength from baseline were detected in men (both p > .25). A significant pioglitazone-by-RT interaction for leg press power was detected in women (p = .006) but not in men (p = .88)., Conclusions: In older overweight and obese adults, a hypocaloric weight loss intervention led to significant declines in lean body mass and appendicular lean body mass. However, in women assigned to RT, leg power significantly improved following the intervention, and muscle strength or power was not adversely effected in the other groups. Pioglitazone potentiated the effect of RT on muscle power in women but not in men; mechanisms underlying this sex effect remain to be determined.

Little is known about the effect of dietary nitrate on the nitrate/nitrite/nitric oxide cycle in older adults. We examined the effect of a 3-day control diet vs high-nitrate diet, with and without a high-nitrate supplement (beetroot juice), on plasma nitrate and nitrite kinetics and blood pressure using a randomized 4-period crossover controlled design. We hypothesized that the high-nitrate diet would show higher levels of plasma nitrate/nitrite and lower blood pressure compared with the control diet, which would be potentiated by the supplement. Participants were 8 normotensive older men and women (5 female, 3 male, 72.5 ± 4.7 years old) with no overt disease or medications that affect nitric oxide metabolism. Plasma nitrate and nitrite levels and blood pressure were measured before and hourly for 3 hours after each meal. The mean daily changes in plasma nitrate and nitrite were significantly different from baseline for both control diet + supplement (P < .001 and P = .017 for nitrate and nitrite, respectively) and high-nitrate diet + supplement (P = .001 and P = .002), but not for control diet (P = .713 and P = .741) or high-nitrate diet (P = .852 and P = .500). Blood pressure decreased from the morning baseline measure to the three 2-hour postmeal follow-up time points for all treatments, but there was no main effect for treatment. In healthy older adults, a high-nitrate supplement consumed at breakfast elevated plasma nitrate and nitrite levels throughout the day. This observation may have practical utility for the timing of intake of a nitrate supplement with physical activity for older adults with vascular dysfunction., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: A number of proteins secreted from adipose tissue, known as adipokines, are involved in the inflammatory process. The expression and secretion of adipokines are altered with obesity, leading to a pro-inflammatory state, with an enhanced vascular immune response. Although weight loss reduces inflammation, the time course for these changes during massive weight loss after bariatric surgery is not well described. We examined the changes in the biomarkers of inflammation after laparoscopic Roux-en-Y gastric bypass (RYGB) in morbidly obese individuals in a university hospital., Methods: The fasting levels of plasma inflammatory adipokines, including leptin, adiponectin, C-reactive protein (CRP), interleukin-6, tumor necrosis factor-α (TNF-α), and soluble receptor 1 for TNF-α were measured before surgery (baseline) and 3 weeks, 3 months, and 6 months after surgery in 15 morbidly obese patients who underwent Roux-en-Y gastric bypass without a major complication., Results: The mean weight loss at 6 months was 25.7% ± 4.5% of the total body weight. The body mass index decreased from a mean of 55.1 ± 6.6 kg/m(2) to 40.5 ± 5.5 kg/m(2). The concentrations of leptin, CRP, and soluble receptor 1 for TNF-α decreased, and the adiponectin levels had increased from the baseline measures by 6 months postoperatively. The baseline and 6-month TNF-α and CRP levels correlated with each other. No other significant associations among the biomarkers were seen., Conclusion: RYGB reduced the pro-inflammatory biomarkers and increased the anti-inflammatory mediators of obesity, independent of the magnitude of weight loss. The lack of correlations between the changes in biomarkers and weight loss suggests that the driving force behind the changes in the inflammatory markers is multifactorial and needs further investigation to clarify the health changes that occur after RYGB., (Copyright © 2011 American Society for Metabolic and Bariatric Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: This study describes baseline physical activity (PA) patterns of individuals with type 2 diabetes mellitus (T2DM) enrolled in the multicenter Look AHEAD Study using an objective measure of PA (accelerometry)., Methods: A total of 2240 participants (age = 59.0 ± 6.8 yr and body mass index (BMI) = 36.5 ± 6.0 kg·m−²) with T2DM provided data for this substudy. Participants were instructed to wear an accelerometer during waking hours for 7 d. Accelerometry data were analyzed to identify periods meeting the criteria of ≥3 MET·min−¹ for Q10 min(moderate- to vigorous-intensity PA (MVPA)) and ≥6 MET·min−¹ for ≥10 min (vigorous-intensity PA (VPA)). Self-reported PA was also assessed with a questionnaire. Accelerometry and self-reported PA data were compared across categories of BMI, sex, race, age, fitness, diabetes medication usage, and history of cardiovascular disease., Results: Self-reported PA was lower at higher levels of BMI, was higher in males, was lowest for African-American/black, and was positively associated with fitness. Multivariate analyses for accelerometer-measured MVPA and VPA showed that more PA bouts per day, minutes per bout, METs per minute, and MET-minutes were associated with higher fitness. For MVPA, bouts per day were higher in men, and METs per minute were higher in women. For VPA, bouts per day was positively associated with increasing age and differed by race/ethnicity. METs per minute were significantly lower at higher levels of BMI and in women. Diabetes medication usage and history of cardiovascular disease were not associated with patterns of PA examined., Conclusions: Results provide information on factors that contribute to PA patterns in adults with T2DM when PA is assessed using both objective and subjective measures. These data may inform interventions to improve PA in adults with T2DM

The startle response has been shown to be useful in studying reactivity to food cues. Following 6h of food deprivation and exposure to neutral and food cues, we examined the role of state craving combined with both a short and long delay of consumption on affect and startle reflex. Participants completed the PANAS, consumed a controlled early morning meal, and experienced 6h of food deprivation. They then reported back to the laboratory, completed a second baseline PANAS, and had their baseline eyeblink EMG startle responses to 100 dB(A) startle probe assessed. Prior to and following the presentation of cues, startle probes were presented and responses were recorded. The PANAS and state craving were also assessed after each cue. Food cues provoked higher levels of state craving than neutral cues and startle responses failed to habituate as quickly to food cues as they did to neutral cues. In addition, cue exposure created the highest NA among high state cravers in the long delay of consumption group. Startle responses differed from NA in that with long delay startle was high irrespective of state craving scores; in the short delay of consumption condition, startle increased linearly with state craving. These results illustrate that state craving and expectations of food availability are important variables in understanding food-related cue reactivity., (2009 Elsevier Ltd. All rights reserved.)

Background: Obesity is a risk factor for impaired physical function and disability, with the degree of impairment most compromised in extreme obesity. Mild-to-moderate weight loss has been shown to improve function in older adults. The impact of laparoscopic Roux-en-Y gastric bypass surgery on weight loss and physical function in morbidly obese individuals was assessed., Methods: This longitudinal, observational study followed up 28 morbidly obese men and women (body mass index > or = 40.0 kg/m(2)) for 12 months after laparoscopic Roux-en-Y gastric bypass. Physical function (self-report using the Fitness Arthritis and Seniors Trial disability questionnaire; performance tasks using the Short Physical Performance Battery and a lateral mobility task); strength (maximal isometric knee torque); and body composition measured using bioelectrical impedance were determined before surgery (baseline) and at 3 weeks, 3 months, 6 months, and 12 months after surgery., Results: The 12-month weight loss was 34.2% (excess weight loss 59.8%), with a mean fat mass loss of 46 kg and a loss of fat free mass of 6.6 kg. The performance tasks and self-reported questionnaire scores had improved by 3 months after surgery compared with baseline, with selected measures showing less impairment and disability in as few as 3 weeks after surgery. Muscle quality, as measured using the maximal torque per kilogram body weight, was greater at 6 months than at baseline., Conclusion: The results of our study have shown that in morbidly obese individuals with a high risk of mobility impairments, surgical procedures to reduce body weight increase mobility and improve performance of daily activities in as few as 3 weeks after gastric bypass surgery.

Background: Little has been reported regarding food and nutrient intake in individuals diagnosed with type 2 diabetes, and most reports have been based on findings in select groups or individuals who self-reported having diabetes., Objective: To describe the baseline food and nutrient intake of the Look AHEAD (Action for Health in Diabetes) trial participants, compare participant intake to national guidelines, and describe demographic and health characteristics associated with food group consumption., Methods: The Look AHEAD trial is evaluating the effects of a lifestyle intervention (calorie control and increased physical activity for weight loss) compared with diabetes support and education on long-term cardiovascular and other health outcomes. Participants are 45 to 75 years old, overweight or obese (body mass index [BMI] > or = 25), and have type 2 diabetes. In this cross-sectional analysis, baseline food consumption was assessed by food frequency questionnaire from 2,757 participants between September 2000 and December 2003., Statistical Analysis: Descriptive statistics were used to summarize intake by demographic characteristics. Kruskal-Wallis tests assessed univariate effects of characteristics on consumption. Multiple linear regression models assessed factors predictive of intake. Least square estimates were based on final models, and logistic regression determined factors predictive of recommended intake., Results: Ninety-three percent of the participants exceeded the recommended percentage of calories from fat, 85% exceeded the saturated fat recommendation, and 92% consumed too much sodium. Also, fewer than half met the minimum recommended servings of fruit, vegetables, dairy, and grains., Conclusions: These participants with pre-existing diabetes did not meet recommended food and nutrition guidelines. These overweight adults diagnosed with diabetes are exceeding recommended intake of fat, saturated fats, and sodium, which may contribute to increasing their risk of cardiovascular disease and other chronic diseases.

Purpose: The purpose of this study was to compare the cost-effectiveness of dietary and exercise interventions in overweight or obese elderly patients with knee osteoarthritis (OA) enrolled in the Arthritis, Diet, and Physical Activity Promotion Trial (ADAPT)., Methods: ADAPT was a single-blinded, controlled trial of 316 adults with knee OA, randomized to one of four groups: Healthy Lifestyle Control group, Diet group, Exercise group, or Exercise and Diet group. A cost analysis was performed from a payer perspective, incorporating those costs and benefits that would be realized by a managed care organization interested in maintaining the health and satisfaction of its enrollees while reducing unnecessary utilization of health care services., Results: The Diet intervention was most cost-effective for reducing weight, at $35 for each percentage point reduction in baseline body weight. The Exercise intervention was most cost-effective for improving mobility, costing $10 for each percentage point improvement in a 6-min walking distance and $9 for each percentage point improvement in the timed stair climbing task. The Exercise and Diet intervention was most cost-effective for improving self-reported function and symptoms of arthritis, costing $24 for each percentage point improvement in subjective function, $20 for each percentage point improvement in self-reported pain, and $56 for each percentage point improvement in self-reported stiffness., Conclusions: The Exercise and Diet intervention consistently yielded the greatest improvements in weight, physical performance, and symptoms of knee OA. However, it was also the most expensive and was the most cost-effective approach only for the subjective outcomes of knee OA (self-reported function, pain, and stiffness). Perceived function and symptoms of knee OA are likely to be stronger drivers of downstream health service utilization than weight, or objective performance measures and may be the most cost-effective in the long term.

The Major Histocompatibility Complex (Mhc) class II DRB locus of vertebrates is highly polymorphic and some alleles may be shared between closely related species as a result of balancing selection in association with resistance to parasites. In this study, we developed a new set of PCR primers to amplify, clone, and sequence overlapping portions of the Mhc class II DRB-like gene from the 5'UTR end to intron 3, including exons 1, 2, and 3 and introns 1 and 2 in four species (20 Humboldt, six African, five Magellanic, and three Galapagos penguins) of penguin from the genus Spheniscus (Sphe). Analysis of gene sequence variation by the neighbor-joining method of 21 Sphe sequences and 20 previously published sequences from four other penguin species revealed overlapping clades within the Sphe species, but species-specific clades for the other penguin species. The overlap of the DRB-like gene sequence variants between the four Sphe species suggests that, despite their allopatric distribution, the Sphe species are closely related and that some shared DRB1 alleles may have undergone a trans-species inheritance because of balancing selection and/or recent rapid speciation. The new primers and PCR assays that we have developed for the identification of the DRB1 DNA and protein sequence variations appear to be useful for the characterization of the molecular evolution of the gene in closely related Penguin species and might be helpful for the assessment of the genetic health and the management of the conservation and captivity of these endangered species.

Objectives: To describe the relationships between proinflammatory biomarkers and self-reported and performance-based physical function and to examine the effect of weight loss on these markers of inflammation., Design: Randomized, longitudinal, clinical study comparing subjects eating an energy-restricted diet and participating in exercise training with a control group., Setting: Community-base participants for the Physical Activity, Inflammation and Body Composition Trial., Participants: Eighty-seven obese (body mass index (BMI) >30.0 kg/m(2)) adults aged 60 and older with knee pain and self-report of osteoarthritis., Measurements: Inflammatory biomarkers (interleukin 6 (IL-6), tumor necrosis factor alpha (TNFalpha), C-reactive protein, and soluble receptors for TNFalpha (sTNFR1 and sTNFR2)) and self-reported (Western Ontario and McMaster University Osteoarthritis Index questionnaire) and performance-based (6-minute walk distance and stair climb time) measures of physical function at baseline and 6 months., Results: Mean (standard error of the mean) weight loss was 8.7% (0.8%) in the intervention group, compared with 0.0% (0.7%) in the control group. sTNFR1 was significantly less in the intervention group than in the control group at 6 months. sTNFR1 and sTNFR2 predicted stair climb time at baseline. Change across the 6-month intervention for sTNFR2 was an independent predictor for change in 6-minute walk distance., Conclusion: These results indicate that an intensive weight-loss intervention in older obese adults with knee pain can help improve inflammatory biomarkers and that changes in these concentrations showed associations with physical function.

Background: The effects of weight loss on muscle function in older adults have not been well studied. This study determined the effects of a 6-month weight-loss intervention on muscle strength and quality in older obese adults with knee osteoarthritis., Methods: Participants were randomized to a weight loss (WL) (n = 44, 70 +/- 6 years) or weight stable (WS) (n = 43, 69 +/- 6 years) group. The WL intervention consisted of weekly educational meetings, a meal replacement diet, and a three-session-per-week structured exercise program to achieve 10%-12% weight loss. The WS intervention included bimonthly group meetings and newsletters. Body composition and knee extensor strength were measured at baseline and after intervention., Results: The WL group decreased body weight, lean body mass, fat mass, and percent body fat (p <.001 for all). Concentric extension strength increased 25% in WL (p >.05), whereas eccentric extension decreased 6% in WS (p =.028). Concentric muscle quality (strength per kg body weight or lean body mass) increased in WL (p <.05), whereas eccentric muscle quality decreased in WS (p <.05). Changes in lean body mass and fat mass were inversely associated with changes in most muscle strength and quality measures (p <.05). Men and women did not differ in response to the intervention in knee strength outcomes., Conclusions: Hypocaloric dieting in combination with exercise training had beneficial effects on muscle strength/quality, despite loss of lean body mass in this sample of older men and women. Greater fat loss was associated with greater gains in muscle strength and quality. More studies are needed regarding the mechanisms by which loss of fat mass increases muscle strength and quality.

Background: Determinants of adherence to lifestyle regimens are ill understood. Attendance to intervention sessions is crucial for patients to acquire knowledge and skills regarding the core elements of an intervention. Therefore, we explored demographic, health-related, and social determinants of high and low attendance to diet and exercise sessions among overweight and obese patients with knee osteoarthritis (> or = 60 years; N = 206)., Methods: The Arthritis, Diet, and Activity Promotion Trial was an 18-month randomized controlled trial on the effectiveness of dietary weight loss and exercise interventions. We conducted chi-square and t-tests, and logistic regression analyses on categories of short- and long-term attendance to intervention sessions., Results: Over the 18-month duration of the study, 60.7% (+/- 28.5) of diet sessions, and 53.2% (+/- 29.0) of exercise sessions were attended. Not being married, low social participation, and single intervention randomization predicted high attendance to diet sessions during months 1-4. Exercising at home, and single intervention randomization predicted high attendance to exercise sessions during months 5-18. High attendance to sessions early in the intervention was a significant determinant of high session attendance thereafter., Conclusions: Offering people a choice where to exercise, and stimulating early intervention session attendance can be effective in improving long-term attendance to both interventions. Several determinants we found may be amenable to change to enhance intervention adherence of future randomized controlled trials involving dietary weight loss and/or physical exercise.

Objective: To determine whether high exercise adherence improved physical function among older adults with knee osteoarthritis (OA) who were overweight or obese., Methods: Associations between exercise adherence, changes in 6-minute walking distance in meters, and self-reported disability (Western Ontario and McMaster Universities Osteoarthritis Index function subscale) after 6 and 18 months were examined among an Arthritis, Diet, and Activity Promotion Trial subsample (n = 134) using multiple linear regression models., Results: Higher exercise adherence was associated with greater improvements in 6-minute walking distance after 6 and 18 months and in disability after 6 months. Pain and body mass index (BMI) contributed, to some extent, to explaining the link between exercise adherence and changes in physical performance and self-reported disability., Conclusion: Higher exercise adherence is associated with improved physical function in overweight and obese older adults with knee OA. This indicates that promoting adherence is clinically relevant when prescribing exercise regimens that also focus on decreasing pain and BMI.

Objective: The Arthritis, Diet, and Activity Promotion Trial (ADAPT) was a randomized, single-blind clinical trial lasting 18 months that was designed to determine whether long-term exercise and dietary weight loss are more effective, either separately or in combination, than usual care in improving physical function, pain, and mobility in older overweight and obese adults with knee osteoarthritis (OA)., Methods: Three hundred sixteen community-dwelling overweight and obese adults ages 60 years and older, with a body mass index of > or =28 kg/m(2), knee pain, radiographic evidence of knee OA, and self-reported physical disability, were randomized into healthy lifestyle (control), diet only, exercise only, and diet plus exercise groups. The primary outcome was self-reported physical function as measured with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Secondary outcomes included weight loss, 6-minute walk distance, stair-climb time, WOMAC pain and stiffness scores, and joint space width., Results: Of the 316 randomized participants, 252 (80%) completed the study. Adherence was as follows: for healthy lifestyle, 73%; for diet only, 72%; for exercise only, 60%; and for diet plus exercise, 64%. In the diet plus exercise group, significant improvements in self-reported physical function (P < 0.05), 6-minute walk distance (P < 0.05), stair-climb time (P < 0.05), and knee pain (P < 0.05) relative to the healthy lifestyle group were observed. In the exercise group, a significant improvement in the 6-minute walk distance (P < 0.05) was observed. The diet-only group was not significantly different from the healthy lifestyle group for any of the functional or mobility measures. The weight-loss groups lost significantly (P < 0.05) more body weight (for diet, 4.9%; for diet plus exercise, 5.7%) than did the healthy lifestyle group (1.2%). Finally, changes in joint space width were not different between the groups., Conclusion: The combination of modest weight loss plus moderate exercise provides better overall improvements in self-reported measures of function and pain and in performance measures of mobility in older overweight and obese adults with knee OA compared with either intervention alone.

Background: Persistent, low-grade inflammation is an independent predictor of several chronic diseases and all-cause mortality., Objective: The intention of this study was to determine the independent and combined effects of diet-induced weight loss and exercise on markers of chronic inflammation., Design: Three hundred sixteen community-dwelling, older (> or = 60 y), overweight or obese [body mass index (in kg/m2) > or = 28], sedentary men and women with radiographic evidence of knee osteoarthritis were randomly assigned to four 18-mo treatments: healthy lifestyle control, diet-induced weight loss, exercise, and diet plus exercise. The exercise intervention consisted of combined weight training and walking for 1 h 3 times/wk. The weight-loss intervention consisted of a weekly session with a registered dietitian to provide education and support for lowering energy intake., Results: The diet-induced weight-loss intervention resulted in significantly greater reductions in concentrations of C-reactive protein (P = 0.01), interleukin 6 (P = 0.009), and soluble tumor necrosis factor alpha receptor 1 (P = 0.007) than did no weight-loss treatment. Changes in soluble tumor necrosis factor alpha receptor 1 but not in C-reactive protein or interleukin 6 correlated with changes in body weight. Exercise training did not have a significant effect on these inflammatory biomarkers, and there was no significant interaction between weight loss and exercise training., Conclusions: These findings provide evidence from a randomized controlled trial that a dietary intervention designed to elicit weight loss reduces overall inflammation in older, obese persons. Additional studies are needed to assess the effects of different modes and intensities of exercise on inflammation.