Summary
Epidemiologic evidence has shown inconsistent findings regarding the relationships between abdominal fatness, as measured by waist circumferences (WC) or waist‐to‐hip ratio (WHR), and risks ...of pre‐ and postmenopausal breast cancer (BC). A dose–response meta‐analysis of prospective studies was conducted to address these issues. Potentially eligible studies were identified by searching PubMed and EMBASE databases, and by carefully reviewing the bibliographies of retrieved publications and related reviews. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated using a random‐effects model. When the most fully adjusted RRs were combined, both WC (14 studies, RR per 10‐cm increase = 1.06, 95% CI: 1.04–1.09, I2 = 29.9%) and WHR (15 studies, RR per 0.1‐unit increase = 1.07, 95% CI: 1.01–1.14, I2 = 52.9%) were significantly positively associated with postmenopausal BC, but neither WC (eight studies, RR per 10‐cm increase = 1.05, 95% CI: 0.99–1.10, I2 = 0%) nor WHR (11 studies, RR per 0.1‐unit increase = 1.07, 95% CI: 0.95–1.21, I2 = 59.7%) were associated with premenopausal BC. The WHR‐postmenopausal BC association lost statistical significance after correcting publication bias (RR per 0.1‐unit increase = 1.06, 95% CI: 0.99–1.13). When considering BMI‐adjusted RRs, WC was associated with both pre‐ (five studies, RR per 10‐cm increase = 1.09, 95% CI: 1.02–1.16, I2 = 0%) and postmenopausal BC (seven studies, RR per 10‐cm increase = 1.05, 95% CI: 1.02–1.08, I2 = 6.3%), whereas WHR was not associated with either pre‐ (seven studies, RR per 0.1‐unit increase = 1.12, 95% CI: 0.94–1.34, I2 = 70.9%) or postmenopausal BC (eight studies, RR per 0.1‐unit increase = 1.05, 95% CI: 0.98–1.13, I2 = 57.3%). Among non‐current (former or never) users of hormone replacement therapy, the summary RR per 10‐cm increase of postmenopausal BC associated with WC was 1.08 (95% CI: 1.03–1.05, I2 = 69.2%, seven studies; BMI‐adjusted RR = 1.05, 95% CI: 1.02–1.09, I2 = 22.8%, four studies). This meta‐analysis indicates that central obesity measured by WC, but not by WHR, is associated with modestly increased risks of both pre‐ and postmenopausal BC independent of general obesity.
Summary
In the present meta-analysis, reductions in the risk of hip fracture with milk consumption were only observed among American adults, but not among Scandinavian adults, possibly because milk ...products are more commonly fortified with vitamin D in the former population than in Scandinavian countries. The reduction in the risk of hip fracture was also observed with yogurt consumption, which is often associated with healthy lifestyles and dietary patterns that contribute to improved bone health.
Introduction
Although dairy products contain bone-beneficial nutrients, the association between dairy consumption and the risk of hip fracture remains equivocal. Fueling this uncertainty, the elevated risk of hip fracture in association with milk consumption was observed in a cohort of Swedish women. A systematic review and meta-analysis of prospective cohort studies was performed to critically evaluate the association, or lack thereof, between dairy consumption (milk, yogurt, and cheese) and the risk of hip fracture.
Methods
A random effects model was used to generate the summary relative risks (RRs) with their 95% confidence intervals (CIs) for the associations of interest.
Results
In the meta-analysis of the highest versus lowest category of consumption, higher consumption of yogurt (RR 0.78, 95% CI 0.68, 0.90), but not milk (RR 0.86, 95% CI 0.73, 1.02) or cheese (RR 0.85, 95% CI 0.66, 1.08), was associated with a lower risk of hip fracture. For milk, the reduced risk of fracture with higher milk consumption was observed in the USA (RR 0.75, 95% CI 0.65, 0.87), but not in Scandinavian countries (RR 1.00, 95% CI 0.85, 1.17). These findings were further supported by the fact that American studies (RR 0.93, 95% CI 0.88, 0.98; per 1 glass/day), but not Scandinavian studies (RR 1.01, 95% CI 0.95, 1.07; per 1 glass/day), demonstrated a linear association between milk consumption and the risk of hip fracture.
Conclusions
The cumulative evidence from prospective cohort studies reassuringly suggests that the risk of hip fracture may not be elevated among people who consume milk, yogurt, and cheese, and that a greater consumption of milk or yogurt may even be associated with a lower risk of hip fracture depending on the factors that may differ across the population of interest.
Milk intake is widely recommended for a healthy diet. Epidemiological studies have suggested that the consumption of dairy products may be associated with a reduction in type 2 diabetes mellitus ...(T2DM). A meta-analysis was conducted to elucidate the association between dairy products consumption and T2DM.
A systematical literature search was done through the Medline database and seven related cohort studies were identified. The adjusted relative risks (RRs) with the highest and the lowest categories from each study were extracted to calculate the combined RR. A least-square trend estimation was applied to assess the dose-response relationships.
A combined RR of 0.86 (95% confidence interval (CI), 0.79-0.92) was revealed on T2DM risk associated to dairy intake, with little evidence of heterogeneity. For subgroup analysis, a combined RR was 0.82 (95% CI, 0.74-0.90), 1.00 (95% CI, 0.89-1.10), 0.95 (95% CI, 0.86-1.05) and 0.83 (95% CI, 0.74-0.93) for the intake of low-fat dairy, high-fat dairy, whole milk and yogurt, respectively. Dose-response analysis showed that T2DM risk could be reduced 5% for total dairy products and 10% for low-fat dairy products.
An inverse association of daily intake of dairy products, especially low-fat dairy, with T2DM was revealed, indicating a beneficial effect of dairy consumption in the prevention of T2DM development.
Individuals with diabetes mellitus (DM) have an increased risk of fracture. Glycemic control is crucial to the management of DM, but there are concerns pertaining to hypoglycemia development in the ...course of glycemic control target achievement. The extent to which glycemic control may affect the risk of fracture remains less defined. Hypoglycemia-induced falls have been suggested to contribute to an elevated risk of fracture in DM patients. In this meta-analysis of observational studies, we aimed to investigate the relative contribution of glycemic control, as measured by glycated hemoglobin (HbA1c), and hypoglycemia to the risk of fracture in DM. The PubMed and Web of Science databases were searched for relevant studies. A random-effects model was used to generate summary relative risks (RRs) and 95% confidence intervals (CIs). Both increased HbA1c levels (RR
per 1% increase
1.08, 95% CI 1.03, 1.14;
n
studies
= 10) and hypoglycemia (RR 1.52, 95% CI 1.23, 1.88;
n
studies
= 8) were associated with an increased risk of fracture. The association between HbA1c levels and the risk of fracture was somewhat nonlinear, with a noticeably increased risk observed at an HbA1c level ≥ 8%. The positive associations of HbA1c levels and hypoglycemia with the risk of fracture did not reach statistical significance in the studies that adjusted for insulin use, hypoglycemia, or falls for the former and in those that adjusted for falls for the latter. In summary, both increased HbA1c levels and hypoglycemia may increase the risk of fracture in patients with DM. The positive association between HbA1c levels and the risk of fracture appears to be, in part, explained by hypoglycemia-induced falls, possibly due to insulin use. The avoidance of hypoglycemia in the course of achieving good glycemic control through the careful selection of glucose-lowering medications may contribute to fracture prevention by reducing the risk of falls related to treatment-induced hypoglycemia.
Due to that the high charge density and small radius render In3+ cation a stronger Lewis acidity, multifunctional nanoporous In-MOFs have become one of the most promising catalysts for their high ...activity. Herein, the solvothermal self-assembly by employing 2,4,6-tri (2,4-dicarboxyphenyl)pyridine (H6TDP) as organic linker leads to a robust honeycomb skeleton of {(CH3)2NH2InIIIPbII(TDP) (H2O)⋅3DMF⋅3H2O}n (NUC-52) with the merits of nanoscopic channels, high porosity (61.3%), large specific surface area, and thermal stability. To the best of our knowledge, this is the first 4p-5p heterometallic {InIIIPbII} cluster-based nano-porous host framework, whose activated state possesses the coexistence of Lewis acid-base sites including 7-coordinated Pb2+ ions, 4-coordinated In3+ ions, uncoordinated carboxyl oxygen atoms, and Npyridine atoms. Performed catalytic experiments exhibited that activated NUC-52 owned the high catalytic activity on the cycloaddition reactions of styrene oxide with CO2 under mild conditions with excellent turnover number (2475) and turnover frequency (619 h−1). Moreover, activated NUC-52 could greatly accelerate the deacetalization-Knoevenagel condensation reactions of benzaldehyde dimethyl acetal and malononitrile. Hence, this work lays down the groundwork for constructing heterometallic cluster-based nanoporous MOFs with excellent Lewis acidic catalysis and chemical stability, which should be ascribed to the reasonable coordination arrangement between organic ligands and distinct metal ions according to the hard–soft acid–base (HSAB) theory.
A highly robust {InPb}-organic framework with Lewis acid-base bifunctional features exhibits high catalytic activity on the cycloaddition reactions of epoxides with CO2 and deacetalization-Knoevenagel condensation reactions. Display omitted
•InPb-cluster-based honeycomb framework of NUC-52 can highly catalyze the cycloaddition of CO2 and deacetalization-Knoevenagel condensation.•Performed catalytic experiments exhibited that activated NUC-52 owned the high catalytic activity on the cycloaddition reactions of styrene oxide with CO2 under mild conditions with excellent turnover number (2475) and turnover frequency (619 h-1). Moreover, activated NUC-52 could greatly accelerate the deacetalization-Knoevenagel condensation reactions of benzaldehyde dimethyl acetal and malononitrile.
Natural convection flows of an electrically conducting fluid under a uniform magnetic field at different angles θ with respect to horizontal plane are investigated numerically in rectangular ...cavities. A new compact finite difference algorithm, involving a second-order compact scheme for the streamfunction-velocity (ψ−u) form of Navier–Stokes equations and a fourth-order compact scheme for the energy equation, is employed to solve the steady-state laminar magnetohydrodynamic (MHD) natural convection problems. Numerical simulations are carried out in a wide range of Rayleigh number (Ra) and Hartmann number (Ha) at the Prandtl number Pr=0.025. The computed results show that the heat transfer is not only determined by the strength of the magnetic field, but also influenced by the inclination angle. Especially, when the aspect ratio (A) is less or more than 1, it is found that the inclination angle plays a great role on flow and heat transfer.
Objectives
The vicious cycle of dynapenia and abdominal obesity may have synergistic detrimental impacts on health. We aim to investigate the prospective association between dynapenic abdominal ...obesity and the risk of heart disease among middle-aged and older adults.
Design
A prospective cohort study.
Setting
English Longitudinal Study of Ageing, 2002–2019.
Participants
A total of 4734 participants aged 50 years and older were included.
Measurements
Individuals were divided into non-dynapenia/non-abdominal obesity (ND/NAO), non-dynapenia/abdominal obesity (ND/AO), dynapenia/non-abdominal obesity (D/NAO), and dynapenia/abdominal obesity (D/AO) according to grip strength and waist circumference at baseline. The Cox proportional hazards models were used to obtain the hazard ratios (HRs) of incident heart disease associated with dynapenia and abdominal obesity after adjusting for potential confounding factors.
Results
During a median follow-up of 9.5 years, 1040 cases of heart disease were recorded. Compared with ND/NAO group, the multivariable HRs were 1.05 (0.92, 1.21) for ND/AO group, 1.31 (0.96, 1.81) for D/NAO group, and 1.39 (1.03, 1.88) for D/AO group. The significant association of D/AO with incident heart disease was detected in women but not in men HR = 1.55 (1.07, 2.24) and 1.06 (0.60, 1.88), respectively. Among middle-aged adults, significant associations of D/NAO and D/AO with incident heart disease were observed HR = 2.46 (1.42, 4.29) and 1.74 (1.02, 2.97), respectively.
Conclusion
Both D/NAO and D/AO might increase the risk of developing heart disease, highlighting the importance of dynapenia and obesity early screening for heart disease prevention.
This meta‐analysis aimed to assess the gender‐specific differences in the relationship between circulating leptin levels and risk of type 2 diabetes. Published prospective studies that reported the ...association of leptin levels with risk of type 2 diabetes for a certain gender or those that reported gender‐specific associations were considered. Dose‐response relationships were assessed by the generalized least squares trend estimation and summary relative risks (RRs) with 95% confidence interval (CI) were computed with the random‐effects model. Stratified and sensitivity analyses were also performed to investigate potential sources of heterogeneity. Overall, 11 prospective studies were identified. The summary RR for an increment in leptin levels of 1‐log ng mL⁻¹ was 1.37 (95% CI, 1.13–1.66) for men and 0.96 (95% CI, 0.90–1.03) for women. The differences between genders were statistically significant (P for interaction = 0.006). Subgroup and sensitivity analyses generally confirmed the robustness of these findings. Furthermore, the increased risk in men appeared non‐linear, with a tendency to plateau at high levels (P for non‐linearity = 0.03). Little evidence of publication bias was found. Collectively, higher leptin levels were found to be associated with elevated risk of type 2 diabetes in men but not in women.
Subwavelength perfect optical absorption structures based on monolayer-graphene are analyzed and demonstrated experimentally. The perfect absorption mechanism is a result of critical coupling ...relating to a guided mode resonance of a low index two-dimensional periodic structure. Peak absorption over 99% at wavelength of 1526.5 nm with full-width at half maximum (FWHM) about 18 nm is demonstrated from a fabricated structure with period of 1230 nm, and the measured results agree well with the simulation results. In addition, the influence of geometrical parameters of the structure and the angular response for oblique incidence are analyzed in detail in the simulation. The demonstrated absorption structure in the presented work has great potential in the design of advanced photo-detectors and modulators.
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