Lifestyle interventions for weight loss are the cornerstone of obesity therapy, yet their optimal design is debated. This is particularly true for postmenopausal women; a population with a high ...prevalence of obesity yet toward whom fewer studies are targeted. We conducted a year‐long, 4‐arm randomized trial among 439 overweight‐to‐obese postmenopausal sedentary women to determine the effects of a calorie‐reduced, low‐fat diet (D), a moderate‐intensity, facility‐based aerobic exercise program (E), or the combination of both interventions (D+E), vs. a no‐lifestyle‐change control (C) on change in body weight and composition. The group‐based dietary intervention had a weight‐reduction goal of ≥10%, and the exercise intervention consisted of a gradual escalation to 45‐min aerobic exercise 5 day/week. Participants were predominantly non‐Hispanic whites (85%) with a mean age of 58.0 ± 5.0 years, a mean BMI of 30.9 ± 4.0 kg/m2 and an average of 47.8 ± 4.4% body fat. Baseline and 12‐month weight and adiposity measures were obtained by staff blinded to participants' intervention assignment. Three hundred and ninety nine women completed the trial (91% retention). Using an intention‐to‐treat analysis, average weight loss at 12 months was −8.5% for the D group (P < 0.0001 vs. C), −2.4% for the E group (P = 0.03 vs. C), and −10.8% for the D+E group (P < 0.0001 vs. C), whereas the C group experienced a nonsignificant −0.8% decrease. BMI, waist circumference, and % body fat were also similarly reduced. Among postmenopausal women, lifestyle‐change involving diet, exercise, or both combined over 1 year improves body weight and adiposity, with the greatest change arising from the combined intervention.
Few studies have examined associations between plasma choline metabolites and risk of colorectal cancer. Therefore, we investigated associations between plasma biomarkers of choline metabolism ...choline, betaine, dimethylglycine, and trimethylamine N-oxide (TMAO) and colorectal cancer risk among postmenopausal women in a case-control study nested within the Women's Health Initiative Observational Study. We selected 835 matched case-control pairs, and cases were further stratified by tumor site (proximal, distal, or rectal) and stage (local/regional or metastatic). Colorectal cancer was assessed by self-report and confirmed by medical records over the mean of 5.2 years of follow-up. Baseline plasma choline metabolites were measured by LC/MS-MS. In multivariable-adjusted conditional logistic regression models, plasma choline tended to be positively associated with rectal cancer risk OR (95% confidence interval, CI)(highest vs. lowest quartile) = 2.44 (0.93-6.40); P trend = 0.08, whereas plasma betaine was inversely associated with colorectal cancer overall 0.68 (0.47-0.99); P trend = 0.01 and with local/regional tumors 0.64 (0.42-0.99); P trend = 0.009. Notably, the plasma betaine:choline ratio was inversely associated with colorectal cancer overall 0.56 (0.39-0.82); P trend = 0.004 as well as with proximal 0.66 (0.41-1.06); P trend = 0.049, rectal 0.27 (0.10-0.78); P trend = 0.02, and local/regional 0.50 (0.33-0.76); P trend = 0.001 tumors. Finally, plasma TMAO, an oxidative derivative of choline produced by intestinal bacteria, was positively associated with rectal cancer 3.38 (1.25-9.16); P trend = 0.02 and with overall colorectal cancer risk among women with lower (vs. higher) plasma vitamin B12 levels (P interaction = 0.003). Collectively, these data suggest that alterations in choline metabolism, which may arise early in disease development, may be associated with higher risk of colorectal cancer. The positive association between plasma TMAO and colorectal cancer risk is consistent with an involvement of the gut microbiome in colorectal cancer pathogenesis.
Overweight or obese breast cancer patients have a worse prognosis compared with normal-weight patients. This may be attributed to hyperinsulinemia and dysregulation of adipokine levels associated ...with overweight and obesity. Here, we evaluate whether low levels of adiponectin and a greater level of insulin resistance are associated with breast cancer mortality and all-cause mortality.
We measured glucose, insulin, and adiponectin levels in fasting serum samples from 527 women enrolled in the Health, Eating, Activity, and Lifestyle (HEAL) Study, a multiethnic, prospective cohort study of women diagnosed with stage I-IIIA breast cancer. We evaluated the association between adiponectin and insulin and glucose levels (expressed as the Homeostatic Model Assessment HOMA score) represented as continuous measures and median split categories, along with breast cancer mortality and all-cause mortality, using Cox proportional hazards models.
Increasing HOMA scores were associated with reduced breast cancer survival (hazard ratio HR, 1.12; 95% CI, 1.05 to 1.20) and reduced all-cause survival (HR, 1.09; 95% CI, 1.02 to 1.15) after adjustment for possible confounders. Higher levels of adiponectin (above the median: 15.5 μg/mL) were associated with longer breast cancer survival (HR, 0.39; 95% CI, 0.15 to 0.95) after adjustment for covariates. A continuous measure of adiponectin was not associated with either breast cancer-specific or all-cause mortality.
Elevated HOMA scores and low levels of adiponectin, both associated with obesity, were associated with increased breast cancer mortality. To the best of our knowledge, this is the first demonstration of the association between low levels of adiponectin and increased breast cancer mortality in breast cancer survivors.
Constructing nanocomposites uniformly anchored on conductive matrix has been regarded as a valid method to improve electrochemical performance. In this work, the SnS2/PCF composite was fabricated by ...a feasible nanocasting strategy, and its microstructure was that the SnS2 nanosheets anchored on porous carbon fibers, which can effectively solve the problem of the poor conductivity and large volume fluctuation of SnS2 during charge/discharge process. Thus, when employed as anode of sodium-ion batteries, the SnS2/PCF composite delivered a high reversible capacity of 425 mA h g−1 after 140 cycles at 0.2 A g−1 and superior rate performance (360 mA h g−1 at 2 A g−1), suggesting the SnS2/PCF is a promising anode material for SIBs.
The SnS2 nanosheets anchored on porous carbon fibers is fabricated by a facile nanocasting strategy (denoted as SnS2/PCF). When used as an anode material for SIBs, it delivers a high specific capacity of 425 mA h g−1 after 140 cycles at a current density of 0.2 A g−1 and superior rate performance (360 mA h g−1 at 2.0 A g−1). Display omitted
•The SnS2/PCF composite was obtained via facile nanocasting strategy.•The SnS2 nanosheets uniformly anchored on PCF.•The composite shows high reversible capacity of 425 mA h g−1 (0.2 A g−1, 140 cycles).•The composite exhibits high rate capacity of 360 mA h g−1 at 2 A g−1.
Using biodegradable blending materials is one of the most effective ways to address plastic pollution but it is hindered by its poor interfacial interaction along with high costs. Herein, an ...envirionmentally friendly filler, camellia seed powder (CSP)−a byproduct of camellia seed after defatting, is reported, which is first served as a compatibilizer in polylactic acid (PLA)/polybutylene succinate (PBS) blends without any other aids or complicated pretreatment, effectively toughening the PLA/PBS blends due to a better interfacial interaction. The results show that the toughness of composites increases with CSP content. With the addition of 30 phr CSP, its impact strength and elongation at break increase by 44.31% and 148.42%, respectively, as compared with the blend without CSP. The combined effects of improved interfacial bonding, reduced particle size of PBS and efficient stress transfer are responsible for the toughness enhancement. The compatibilization mechanism is proposed that ─COOH groups in PLA and PBS react with ─NH2 in CSP. The above finding of CSP as a compatibilizer provides a facile and inexpensive strategy in the fabrication of high‐performance biodegradable materials.
This work reports an environment‐friendly filler, camellia seed powder (CSP), is first utilized to reinforce and modify PLA/PBS blends without any other aids, owing to some of the ─COOH in PLA and PBS reacts with ─NH2 in CSP to form ─C─N─ bond.
Background Comprehensive lifestyle interventions are effective in preventing diabetes and restoring glucose regulation; however, the key stimulus for change has not been identified and effects in ...older individuals are not established. The aim of the study was to investigate the independent and combined effects of dietary weight loss and exercise on insulin sensitivity and restoration of normal fasting glucose in middle-aged and older women. Design Four-arm RCT, conducted between 2005 and 2009 and data analyzed in 2010. Setting/participants 439 inactive, overweight/obese postmenopausal women. Interventions Women were assigned to: dietary weight loss ( n =118); exercise ( n =117); exercise+diet ( n =117); or control ( n =87). The diet intervention was a group-based reduced-calorie program with a 10% weight-loss goal. The exercise intervention was 45 min/day, 5 days/week of moderate-to-vigorous intensity aerobic activity. Main outcome measures 12-month change in serum insulin, C-peptide, fasting glucose, and whole body insulin resistance (HOMA-IR). Results A significant improvement in HOMA-IR was detected in the diet (–24%, p <0.001) and exercise+ diet (–26%, p <0.001) groups but not in the exercise (–9%, p =0.22) group compared with controls (–2%); these effects were similar in middle-aged (50–60 years) and older women (aged 60–75 years). Among those with impaired fasting glucose (5.6–6.9 mmol/L) at baseline ( n =143; 33%), the odds (95% CI) of regressing to normal fasting glucose after adjusting for weight loss and baseline levels were 2.5 (0.8, 8.4); 2.76 (0.8, 10.0); and 3.1 (1.0, 9.9) in the diet, exercise+diet, and exercise group, respectively, compared with controls. Conclusions Dietary weight loss, with or without exercise, significantly improved insulin resistance. Older women derived as much benefit as did the younger postmenopausal women. Trial registration This study is registered at Clinicaltrials.gov NCT00470119.
Obese and sedentary persons have increased risk for cancer; inflammation is a hypothesized mechanism. We examined the effects of a caloric restriction weight loss diet and exercise on inflammatory ...biomarkers in 439 women. Overweight and obese postmenopausal women were randomized to 1-year: caloric restriction diet (goal of 10% weight loss, N = 118), aerobic exercise (225 min/wk of moderate-to-vigorous activity, N = 117), combined diet + exercise (N = 117), or control (N = 87). Baseline and 1-year high-sensitivity C-reactive protein (hs-CRP), serum amyloid A (SAA), interleukin-6 (IL-6), leukocyte, and neutrophil levels were measured by investigators blind to group. Inflammatory biomarker changes were compared using generalized estimating equations. Models were adjusted for baseline body mass index (BMI), race/ethnicity, and age. Four hundred and thirty-eight (N = 1 in diet + exercise group was excluded) were analyzed. Relative to controls, hs-CRP decreased by geometric mean (95% confidence interval, P value): 0.92 mg/L (0.53-1.31, P < 0.001) in the diet and 0.87 mg/L (0.51-1.23, P < 0.0001) in the diet + exercise groups. IL-6 decreased by 0.34 pg/mL (0.13-0.55, P = 0.001) in the diet and 0.32 pg/mL (0.15-0.49, P < 0.001) in the diet + exercise groups. Neutrophil counts decreased by 0.31 × 10(9)/L (0.09-0.54, P = 0.006) in the diet and 0.30 × 10(9)/L (0.09-0.50, P = 0.005) in the diet + exercise groups. Diet and diet + exercise participants with 5% or more weight loss reduced inflammatory biomarkers (hs-CRP, SAA, and IL-6) compared with controls. The diet and diet + exercise groups reduced hs-CRP in all subgroups of baseline BMI, waist circumference, CRP level, and fasting glucose. Our findings indicate that a caloric restriction weight loss diet with or without exercise reduces biomarkers of inflammation in postmenopausal women, with potential clinical significance for cancer risk reduction.
Estrogens and androgens are elevated in obesity and associated with increased postmenopausal breast cancer risk, but the effect of weight loss on these biomarkers is unknown. We evaluated the ...individual and combined effects of a reduced-calorie weight loss diet and exercise on serum sex hormones in overweight and obese postmenopausal women.
We conducted a single-blind, 12-month, randomized controlled trial from 2005 to 2009. Participants (age 50 to 75 years; body mass index > 25.0 kg/m(2), exercising < 100 minutes/wk) were randomly assigned using a computer-generated sequence to (1) reduced-calorie weight loss diet ("diet"; n = 118), (2) moderate- to vigorous-intensity aerobic exercise ("exercise"; n = 117), (3) combined reduced-calorie weight loss diet and moderate- to vigorous-intensity aerobic exercise ("diet + exercise"; n = 117), or (4) control (n = 87). Outcomes were estrone concentration (primary) and estradiol, free estradiol, total testosterone, free testosterone, androstenedione, and sex hormone-binding globulin (SHBG) concentrations (secondary).
Mean age and body mass index were 58 years and 30.9 kg/m(2), respectively. Compared with controls, estrone decreased 9.6% (P = .001) with diet, 5.5% (P = .01) with exercise, and 11.1% (P < .001) with diet + exercise. Estradiol decreased 16.2% (P < .001) with diet, 4.9% (P = .10) with exercise, and 20.3% (P < .001) with diet + exercise. SHBG increased 22.4% (P < .001) with diet and 25.8% (P < .001) with diet + exercise. Free estradiol decreased 21.4% (P < .001) with diet and 26.0% (P < .001) with diet + exercise. Free testosterone decreased 10.0% (P < .001) with diet and 15.6% (P < .001) with diet + exercise. Greater weight loss produced stronger effects on estrogens and SHBG.
Weight loss significantly lowered serum estrogens and free testosterone, supporting weight loss for risk reduction through lowering exposure to breast cancer biomarkers.
In this paper, poly(butylene succinate) (PBS) with a low melting point and a similar performance to polyethylene is employed as a printing material; talc is introduced into the matrix to enhance the ...melt strength of pure PBS during printing. The PBS/talc composite 3D printing filament is prepared by melt extrusion, and the thermal, mechanical, morphological, and rheological properties of the composites are investigated. The results show that the addition of talc to PBS leads to an increase in crystallization temperature. In addition, the tensile and flexural strengths of the injection‐molded specimens increase when the talc concentration increases. However, the mechanical properties of the printed specimens exhibit an opposite variation trend due to their distinct forming process. The printing temperature is 135 °C, which is far lower than those of commercial grade polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) printing filaments. Scanning electron microscopy (SEM) images show that increasing the talc concentration creates better printed formability and well‐organized fracture surface structures. By comparing printed fishbones, the results suggest that the presence of talc leads to a good printing performance with the composite. Furthermore, the rheological results reveal that η*, G′, and G″ are enhanced by the addition of talc.
PBS, which is an eco‐friendly polyester with broad prospects, is successfully applied to 3D printing applications by blending with talc. The experimental results indicate that the composites are enhanced by talc addition and that the composites exhibit good formability at low printing temperatures. These eco‐friendly filaments may further broaden the range of 3D printing materials.
Increased physical activity is associated with decreased risk of several types of cancer, but underlying mechanisms are poorly understood. Angiogenesis, in which new blood vessels are formed, is ...common to adipose tissue formation/remodeling and tumor vascularization.
We examined effects of a 12-month 45 minutes/day, 5 days/week moderate-intensity aerobic exercise intervention on four serum markers of angiogenesis in 173 sedentary, overweight, postmenopausal women, 50 to 75 years, randomized to intervention versus stretching control. Circulating levels of positive regulators of angiogenesis VEGF, osteopontin (OPN), plasminogen activator inhibitor-1 (PAI-1), and the negative regulator pigment epithelium-derived factor (PEDF), were measured by immunoassay at baseline and 12 months. Changes were compared using generalized estimating equations, adjusting for baseline levels of analytes and body mass index (BMI).
VEGF, OPN, or PAI-1 levels did not differ by intervention arm. Participants randomized to exercise significantly reduced PEDF (-3.7%) versus controls (+3.0%; P = 0.009). Reductions in fat mass were significantly associated with reductions in PAI-1 (Ptrend = 0.03; Ptrend = 0.02) and PEDF (Ptrend = 0.002; Ptrend = 0.01) compared with controls, or to those who gained any fat mass respectively. There was a significant association between decreases in VO2max, and increased reductions in PEDF (Ptrend = 0.03), compared with participants who increased their level of fitness.
Fat loss reduces circulating PAI-1 and PEDF. Changes in VO2max are associated with alterations in PEDF, but these associations are complex.
Unexpected reductions in PEDF with decreasing fat mass, and with decreasing VO2max, warrant further study, including examining the effects of different types and intensities of exercise; and role of dietary weight-loss with and without exercise.
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