Colon and rectal cancer risk after bariatric surgery in a multicountry Nordic cohort study

Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980–2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28–1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92–1.39) and 1.55 (95% CI 1.04–2.31) 10–14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83–1.52; HR 1.08, 95% CI 0.79–1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker.     

Biomedical microelectromechanical systems (BioMEMS): Revolution in drug delivery and analytical techniques

Advancement in microelectromechanical system has facilitated the microfabrication of polymeric substrates and the development of the novel class of controlled drug delivery devices. These vehicles have specifically tailored three dimensional physical and chemical features which together, provide the capacity to target cell, stimulate unidirectional controlled release of therapeutics and augment permeation across the barriers. Apart from drug delivery devices microfabrication technology’s offer exciting prospects to generate biomimetic gastrointestinal tract models. BioMEMS are capable of analysing biochemical liquid sample like solution of metabolites, macromolecules, proteins, nucleic acid, cells and viruses. This review summarized multidisciplinary application of biomedical microelectromechanical systems in drug delivery and its potential in analytical procedures.     

Sensitivity of the environmental costs of air pollution caused by SOx,NOx, and PM from power plants applied to the power mix configuration in South Korea

In the 6th Basic Plan for Long-Term Electricity Supply and Demand (6th BPE) for Korea, for the first time, the environmental costs of air pollution caused by oxides of sulfur (SOx), oxides of nitrogen (NOx), and particulate matters (PM) from power plants were estimated and included. However, several deficiencies in evaluating the environmental costs were found. In this study, (1) the validity of the environmental costs used in the 6th BPE was assessed, (2) a systematic approach was suggested and used to improve the environmental costs estimation, and (3) the sensitivity of the cost of generating electricity to the environmental costs by fuel type with the proposed approach was discussed. We found that the applied environmental costs used in the 6th BPE did not fully include the demographic characteristics of Korea. By applying more realistic parameter values, it was found that the newly estimated environmental cost was about 23 times higher than the cost estimated in the original 6th BPE for coal-fired power plants and about 1.5 times higher for liquefied natural gas (LNG)-fired power plants, suggesting that LNG-fired power plants are more economical if using more realistic environmental costs. Thus, it is critical to check the validity of parameter values when calculating environmental costs.