These data suggest that hyperinsulinemia is an independent risk factor for breast cancer and may have a substantial role in explaining the obesity-breast cancer relationship.

Obesity is a risk factor for colorectal cancer, and hyperinsulinemia, a common condition in obese patients, may underlie this relationship. Insulin, in addition to its metabolic effects, has promitotic and antiapoptotic activity that may be tumorigenic. Insulin-like growth factor (IGF)-I, a related hormone, shares sequence homology with insulin, and has even stronger mitogenic effects. However, few prospective colorectal cancer studies directly measured fasting insulin, and none evaluated free IGF-I, or endogenous estradiol, a potential cofactor in postmenopausal women. Therefore, we conducted a casecohort investigation of colorectal cancer among nondiabetic subjects enrolled in the Women's Health Initiative Observational Study, a prospective cohort of 93,676 postmenopausal women. Fasting baseline serum specimens from all incident colorectal cancer cases (n = 438) and a random subcohort (n = 816) of Women's Health Initiative Observational Study subjects were tested for insulin, glucose, total IGF-I, free IGF-I, IGF binding protein-3, and estradiol. Comparing extreme quartiles, insulin [hazard ratio (HR) q4-q1 , 1.73; 95% confidence interval (CI), 1.16-2.57; P trend = 0.005], waist circumference (HR q4-q1 , 1.82; 95% CI, 1.22-2.70; P trend = 0.001), and free IGF-I (HR q4-q1 , 1.35; 95% CI, 0.92-1.98; P trend = 0.05) were each associated with colorectal cancer incidence in multivariate models. However, these associations each became nonsignificant when adjusted for one another. Endogenous estradiol levels, in contrast, were positively associated with risk of colorectal cancer (HR comparing high versus low levels, 1.53; 95% CI, 1.05-2.22), even after control for insulin, free IGF-I, and waist circumference. These data suggest the existence of at least two independent biological pathways that are related to colorectal cancer: one that involves endogenous estradiol, and a second pathway broadly associated with obesity, hyperinsulinemia, and free IGF-I. [Cancer Res 2008;68(1):329-37]

Obesity is a major risk factor for endometrial cancer, a relationship thought to be largely explained by the prevalence of high estrogen levels in obese women. Obesity is also associated with high levels of insulin, a known mitogen. However, no prospective studies have directly assessed whether insulin and/or insulin-like growth factor-I (IGF-I), a related hormone, are associated with endometrial cancer while accounting for estrogen levels. We therefore conducted a case-cohort study of incident endometrial cancer in the Women's Health Initiative Observational Study, a prospective cohort of 93,676 postmenopausal women. The study involved all 250 incident cases and a random subcohort of 465 subjects for comparison. Insulin, total IGF-I, free IGF-I, IGF-binding protein-3, glucose, and estradiol levels were measured in fasting baseline serum specimens. Cox models were used to estimate associations with endometrial cancer, particularly endometrioid adenocarcinomas, the main histologic type (n = 205). Our data showed that insulin levels were positively associated with endometrioid adenocarcinoma [hazard ratio contrasting highest versus lowest quartile (HR q4-q1 ), 2.33; 95% confidence interval (95% CI), 1.13-4.82] among women not using hormone therapy after adjustment for age and estradiol. Free IGF-I was inversely associated with endometrioid adenocarcinoma (HR q4-q1 , 0.53; 95% CI, 0.31-0.90) after adjustment for age, hormone therapy use, and estradiol. Both of these associations were stronger among overweight/obese women, especially the association between insulin and endometrioid adenocarcinoma (HR q4-q1 , 4.30; 95% CI, 1.62-11.43). These data indicate that hyperinsulinemia may represent a risk factor for endometrioid adenocarcinoma that is independent of estradiol. Free IGF-I levels were inversely associated with endometrioid adenocarcinoma, consistent with prior cross-sectional data. (Cancer Epidemiol Biomarkers Prev 2008;17(4):921 -9)

Zinc vacancy (VZn) is successfully introduced into 3D hierarchical ZnIn2S4 (3D‐ZIS). The photo‐electrochemical experiments demonstrate that the charge separation and carrier transfer are more efficient in the 3D‐ZIS with rich VZn. Of note, for the first time, it is found that VZn can decrease the carrier transport activation energy (CTAE), from 1.14 eV for Bulk‐ZIS (Bulk ZnIn2S4) to 0.93 eV for 3D‐ZIS, which may provide a feasible platform for further understanding the mechanism of photocatalytic CO2 reduction. In situ Fourier transform infrared (FT‐IR) results reveal that the presence of rich VZn ensures CO2 chemical activation, promoting single‐electron reduction of CO2 to CO2−. In addition, in situ FT‐IR and CO2 temperature programmed desorption results show that VZn can promote the formation of surface hydroxyl. To the best of current knowledge, there are no reports on the photoreduction of CO2 simply by virtue of 3D‐ZIS with VZn and few literature reports on the photocatalytic reduction of CO2 concerned with CTAE. Additionally, this work finds that surface hydroxyl may play a crucial role in the process of CO2 photoreduction. The work may provide some novel ways to ameliorate solar energy conversion performance and a better understanding of photoreaction mechanisms.

A covalent organic framework (Tp-PTO-COF) with carbonyl active sites was proposed as a novel cathode material and successfully applied in aqueous rechargeable zinc-ion batteries (ZIBs).

To reduce the ever-growing greenhouse gas CO 2 , CO 2 utilization is considered with much more promise as it could convert CO 2 into value-added industrial products and achieve carbon cyclic utilization. Therefore, a high performance catalyst is supposed to be an important prerequisite to achieve CO 2 activation and conversion. In this work, a new metal-free bifunctional porous organic framework (POF) heterogeneous catalyst, POF-PNA-Br − , has been successfully prepared with a two-step method. Because of the synergy of the carboxylic acid group as a Brønsted acidic site and the Br − anion generated from pyridine-based ionic liquids as the nucleophilic site, POF-PNA-Br − as a bifunctional metal-free environmentally friendly heterogeneous catalyst displayed an efficient catalytic performance for the cycloaddition reaction of CO 2 and epoxide to form cyclic carbonate under mild and cocatalyst-free conditions. This work provides an efficient new method for the design and synthesis of bifunctional POF catalysts for the CO 2 cycloaddition reaction.

No abstract

Herein, we report a strategy to construct highly efficient perfluorooctanoic acid (PFOA) adsorbents by installing synergistic electrostatic/hydrophobic sites onto porous organic polymers (POPs). The constructed model material of PAF-1-NDMB (NDMB = N,N-dimethyl-butylamine) demonstrates an exceptionally high PFOA uptake capacity over 2000 mg g−1, which is 14.8 times enhancement compared with its parent material of PAF-1. And it is 32.0 and 24.1 times higher than benchmark materials of DFB-CDP (β-cyclodextrin (β-CD)-based polymer network) and activated carbon under the same conditions. Furthermore, PAF-1-NDMB exhibits the highest k2 value of 24,000 g mg−1 h−1 among all reported PFOA sorbents. And it can remove 99.99% PFOA from 1000 ppb to <70 ppt within 2 min, which is lower than the advisory level of Environmental Protection Agency of United States. This work thus not only provides a generic approach for constructing PFOA adsorbents, but also develops POPs as a platform for PFOA capture.