Objective To explore clinical value of cardiac MRI feature tracking (CMR-FT) in evaluation of left ventricular global and regional myocardial strain in hypertrophic cardiomyopathy (HCM).Methods Totally 60 patients with HCM (HCM group) and 10 healthy volunteers (control group) were enrolled and underwent cardiac MR.MR Sequences included fast imaging employing steady state acquisition (FIESTA) and late gadalinum enhancement (LGE) at ventricular short-axis,two-chamber and four-chamber planes.The patients in HCM group were divided into LGE negative subgroup and LGE positive subgroup.CMR-FT processing software was used to measure myocardial global radial peak strain (GPSR),global circumferential peak strain (GPSC) and global longitudinal peak strain (GPSL).The radial,circumferential and longitudinal peak strain (PSR,PSC and PSL) at the apex,middle and basal parts of left ventricular were also measured as well.Resuits GPSR,GPSC,GPSL in LGE positive subgroup,LGE negative subgroup and control group had significant differences (all P＜0.05),and showed upward trends.Except PSL at the apex had no significent difference among three groups,PSR,PSC and PSL at the apex,middle and basal parts had significant differences (all P＜0.05),and also showed upward trends.There were positive correlations between the LVEF,SV and GPSR,GPSC,GPSL (all P＜0.05).The area under ROC curve of GPSR,GPSC and GPSL in diagnosis of HCM were 0.79,0.82,0.77 (all P＜0.05),and the area under ROC curve of GPSC was the largest.Conclusion The CMR-FT technology can find myocardial strain dysfunction in HCM sensitively,and the longitudinal strain is damaged earlier or worse than circumferential and radial strains.

Breast cancer is the most common spontaneous malignancy in women, causing a serious threat to women's health. Experimental animal models have been important research tools in bringing insights into the related mechanisms of breast cancer, as well as in delivering improved therapies for the disease. To reveal the pathogenesis of various breast cancers and facilitate the development of new drugs,ideal animal models of breast cancer should share some common tumor molecular characteristics and biological behavior with that of human breast cancer. In this review,five types of experimental animal breast cancer models were included, which may provide a basis for research on diagnosis and treatment of human breast cancer.

Particulate matter (PM) is the main air pollutant in China. Due to its wide distribution and difficulties in control, PM has been widely concerned. PM mainly enters human body through respiratory exposure and can cause a variety of health problems. Recent studies have shown that PM exposure is also associated with the occurrence and development of digestive system diseases, as it can enter human body indirectly through the respiratory tract or directly through the digestive tract. Gut microbiota (GM) is a group of microorganisms located in the intestinal epithelium mucosa and intestinal lumen. GM is large in number and rich in functions, and its homeostasis plays an important role in the intestinal health of individuals and even the health of the body. Because GM may mediate the health effects induced by environmental factors, more and more studies have focused on the effects of ambient PM on GM. In this review, we summarized the effects of a variety of ambient PM on GM homeostasis, focusing on five major phyla including Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Verrucomicrobia, and discussed their main functions and the effects of PM on their homeostasis and abundance.