Objective To study the co-effects of methylene blue(MB) and exposure with the cold light source on cell DNA damage, and to explore the mechanism involved. Methods The alkaline single cell gel electrophoresis was used to determine cell DNA damage. Apoptosis of the cells was determined by flow cytometry analysis using Annexin V-FITC/PI staining. DCFH-DA probe was used to determine endocellular Reactive Oxygen Species (ROS). Results The levels of DNA damage in the SGC7901 adenocarcinoma cells treated with methylene blue in the light were significantly increased compared to that of control ( F = 8.39, P＜0.05 ). The DNA damage levels were related to the length of time of light exposure, and the damage was recovered to a certain level after light withdrew. Cell apoptosis ( x2=7.71,P ＜0.05)and endocellular ROS level (F = 34.11, P＜0.01＝ increased significantly in the exposure group. Conclusions Methylene blue chromoendoscopy can induce DNA damage and cell apoptosis, and the mechanism may be associated with ROS produced by the photochemical reaction.

Objective:Based on the perspective of supply and demand balance, to analyze the implementation effects of primary-feature medical services measures in medical alliances.Methods:From July to September 2019, two regions with different levels of economic development were chosen, and from each region one leading hospital and two community health service centers/township hospitals were selected from its medical alliance. A total of 213 medical staff and 703 residents were surveyed, to learn their awareness and performance appraisal of these feature services.Frequency and proportion were calculated in a descriptive statistical analysis. The scores of the performance appraisal of both supply and demand sides were tested by independent sample t. Results:In the performance appraisal of such measures, the average scoring by medical staff was 4.39±0.07, and that by residents was 3.85±0.06; the residents were more concerned with service capabilities and contents, while medical staff were more concerned with service content and delivery mode; supply and demand sides were found with consensus in terms of improving the medical service quality of chronic diseases in primary level and service accessibility.Conclusions:The county-level medical alliances should focus on enhancing their capacity of primary medical services, and improving their primary service mode with the help of medical insurance institutions. Meanwhile, it is imperative to optimize the primary medical service policy in view of supply and demand balance.

Ensuring food safety is paramount worldwide.Developing effective detection methods to ensure food safety can be challenging owing to trace hazards,long detection time,and resource-poor sites,in addition to the matrix effects of food.Personal glucose meter(PGM),a classic point-of-care testing device,possesses unique application advantages,demonstrating promise in food safety.Currently,many studies have used PGM-based biosensors and signal amplification technologies to achieve sensitive and specific detection of food hazards.Signal amplification technologies have the potential to greatly improve the analytical performance and integration of PGMs with biosensors,which is crucial for solving the challenges associated with the use of PGMs for food safety analysis.This review introduces the basic detection principle of a PGM-based sensing strategy,which consists of three key factors:target recog-nition,signal transduction,and signal output.Representative studies of existing PGM-based sensing strategies combined with various signal amplification technologies(nanomaterial-loaded multienzyme labeling,nucleic acid reaction,DNAzyme catalysis,responsive nanomaterial encapsulation,and others)in the field of food safety detection are reviewed.Future perspectives and potential opportunities and challenges associated with PGMs in the field of food safety are discussed.Despite the need for complex sample preparation and the lack of standardization in the field,using PGMs in combination with signal amplification technology shows promise as a rapid and cost-effective method for food safety hazard analysis.