Etiologic heterogeneity of clear-cell and papillary renal cell carcinoma in the Netherlands Cohort Study
INTERNATIONAL JOURNAL OF CANCER
Authors: van de Pol, Jeroen A. A.; George, Lisa; van den Brandt, Piet A.; Baldewijns, Marcella M. L. L.; Schouten, Leo J.
At present, mostly case-control and retrospective studies have investigated the association between etiologic risk factors and the development of histologic subtypes of renal cell carcinoma (RCC). Therefore, we assessed the heterogeneity between body mass index (BMI), cigarette smoking, alcohol consumption and hypertension across clear-cell RCC (ccRCC) and papillary RCC (pRCC) risk in the prospective Netherlands Cohort Study on diet and cancer. In 1986, 120 852 participants aged 55 to 69 completed a self-administered questionnaire on diet and other risk factors for cancer. Participants were followed up for cancer through record linkage. Tumor histology was assessed through centralized revision by two experienced uropathologists. After 20.3 years of follow-up, 384 histologically verified RCC cases, including 315 ccRCC and 46 pRCC cases and 4144 subcohort members were eligible for case-cohort analysis. Hazard ratios and 95% confidence intervals were estimated by multivariable-adjusted proportional hazards models. Overall, BMI was associated positively with ccRCC risk, but inversely with pRCC risk. Cigarette smoking was associated with an increased ccRCC, but a decreased pRCC risk. Alcohol consumption was inversely associated with both ccRCC and pRCC risk. Hypertension was associated with an increased risk of both ccRCC and pRCC. Statistically significant etiologic heterogeneity was observed for BMI, BMI change since age 20, and smoking duration in current smokers across ccRCC and pRCC risk. In conclusion, we observed potential heterogeneity for BMI, BMI change and smoking duration across ccRCC and pRCC risk.
Steric hindrance effect and kinetic investigation for ionic liquid catalyzed synthesis of 4-hydroxy-2-butanone via aldol reaction
CHEMICAL ENGINEERING SCIENCE
Authors: Wang, Gang; Cai, Guangming
4-Hydroxy-2-butanone as important chemical intermediate in the field of both pharmaceutical and food industries is traditionally synthesized from formaldehyde and acetone via aldol reaction with relatively low selectivity due to the heavy side reactions. Herein, series of basic ionic liquids with different sterically hindered cations were prepared for this reaction process. The catalytic performance evaluation results revealed the selectivity of 4-hydroxy-2-butanone could be enhanced with the extension of alkyl chain length substituted in the cation of ionic liquid and increasing number of substituted alkyl group. And the tetraoctyl ammonium hydroxide ([N8,8,8,8]OH) was identified as the optimal ionic liquid catalyst with selectivity of 91.1% toward 4-hydroxy-2-butanone at 40 degrees C. The kinetic studies indicated the forma-tion of 4-hydroxy-2-butanone was first-order dependent on both acetone and formaldehyde concentrations, with the lowest activation barrier of 49.8 kJ/mol among all steps. (c) 2020 Elsevier Ltd. All rights reserved.