Physical activity and cancer risk: a dose-response analysis for the Global Burden of Disease Study 2019.

OBJECTIVE: Adopting a healthy lifestyle, including regular physical activity, is widely believed to decrease cancer risk. This study aimed to quantitatively establish the dose-response relationships between total physical activity and the risk of breast, colon, lung, gastric, and liver cancers. METHODS: A systematic review and dose-response analysis were conducted using PubMed and Embase from January 1, 1980 to March 20, 2023. Prospective cohort studies that examined the association between physical activity and the risks of any of the 5 outcomes were included. The search was confined to publications in the English language with a specific focus on human studies. Physical activity is standardized by using the data from US National Health and Nutrition Examination Surveys (NHANES) and the Global Burden of Disease 2019 database. RESULTS: A total of 98 studies, involving a combined population of 16,418,361 individuals, were included in the analysis. Among the included studies, 57 focused on breast cancer, 17 on lung cancer, 23 on colon cancer, 5 on gastric cancer, and 7 on liver cancer. Overall, elevated levels of physical activity exhibited an inverse correlation with the risk of cancer. The dose-response curve for lung cancer exhibited a non-linear pattern, with the greatest benefit risk reduction observed at 13,200 MET-minutes/week of physical activity, resulting in a 14.7% reduction in risk (relative risk 0.853, uncertainty interval 0.798 to 0.912) compared to the inactive population. In contrast, the dose-response curves for colon, gastric, breast, and liver cancers showed linear associations, indicating that heightened levels of total physical activity were consistently associated with reduced cancer risks. However, the increase in physical activity yielded a smaller risk reduction for colon and gastric cancers compared to breast and liver cancers. Compared to individuals with insufficient activity (total activity level < 600 MET-minutes/week), individuals with high levels of activity (≥ 8,000 MET-minutes/week) experienced a 10.3% (0.897, 0.860 to 0.934) risk reduction for breast cancer; 5.9% (0.941, 0.884 to 1.001) for lung cancer; 7.1% (0.929, 0.909 to 0.949) for colon cancer; 5.1% (0.949, 0.908 to 0.992) for gastric cancer; 17.1% (0.829, 0.760 to 0.903) for liver cancer. CONCLUSIONS: This study demonstrated a significant inverse relationship between total physical activity and the risk of breast, gastric, liver, colon, and lung cancers.

Comparative assessment of genotyping methods for study genetic diversity of Fusarium oxysporum isolates.

In this study, we evaluated three PCR-based methods for the molecular typing of nonpathogenic Fusarium oxysporum isolates: random amplified polymorphic DNA (RAPD), polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and amplified fragment length polymorphism (AFLP). The analyses were performed using 64 isolates of F. oxysporum collected from cotton-producing areas in Egypt. A number of polymorphic RAPD, PCR-RFLP and AFLP bands were scored in all isolates and the genetic similarity among them was assessed. Clustering analysis separated the isolates into two main groups, with similarities ranging from 87 to 100% for RAPD, 80 to 100% for PCR-RFLP and 88 to 97% for AFLP, respectively. The obtained data suggested that all three types of markers are equally informative, but the three assays differed in the amount of detected polymorphic bands. AFLP fingerprinting was also found to be more differentiating than other techniques for the typing of F. oxysporum populations.