[Evaluation of the right ventricular function in patients with pneumoconiosis by three-dimensional speckle-tracking imaging].

Objective: To evaluate the changes of right ventricular function in patients with pneumoconiosis in different stages using three-dimensional speckle-tracking imaging (3D-STI) . Methods: In June 2020, 114 pneumoconiosis patients were selected as subjects, including 45 patients in stage Ⅰ pneumoconiosis group, 36 patients in stage Ⅱ pneumoconiosis group and 33 patients in stage Ⅲ pneumoconiosis group. Fifty healthy subjects were enrolled and served as control group. The longitudinal strain (LS) , radial strain (RS) and circumferential strain (CS) of free wall middle and basal segment of right ventricular were collected and compared. The right ventricular global longitudinal strain (GLS) , right ventricular global circumferential strain (GCS) , right ventricular ejection fraction (RVEF) , right ventricular global radial strain (GRS) , the rate of fractional area change (FAC) , the tricuspid valve systolic peak velocity (TVSPV) and the pulmonary artery systolic pressure (PASP) of each subject in the groups were collected and compared by 3D-STI. Results: The LS and RS of the right ventricular basal segment of patients in stage Ⅱ pneumoconiosis group were significantly lower than those of control group (P<0.0125) . The LS, CS, RS of the right ventricular basal segment and RS of right ventricular middle segment of patients in stage Ⅲ pneumoconiosis group were significantly lower than those of control group (P<0.0125) . The LS, CS and RS of the right ventricular basal segment of patients in stage Ⅰ pneumoconiosis group were significantly higher than those of stage Ⅲ pneumoconiosis group (P<0.0125) , and the RS of the right ventricular basal segment of patients in stage Ⅱ pneumoconiosis group was significantly higher than that of stage Ⅲ pneumoconiosis group (P<0.0125) . The levels of RVEF and GLS of patients in stage Ⅱ and stage Ⅲ pneumoconiosis group were significantly lower than those of control group (P<0.0125) , while the levels of PASP were significantly higher than that of control group (P<0.0125) . The levels of FAC and TVSPV of patients in stage Ⅲ pneumoconiosis group were significantly lower than those of control group (P<0.0125) . The levels of RVEF, GLS and FAC of patients in stage Ⅰ pneumoconiosis group were significantly higher those that of stage Ⅲ pneumoconiosis group (P<0.0125) , and the PASP level was significantly lower than that of stage Ⅲ pneumoconiosis group (P<0.0125) . The FAC level of patients in stage Ⅱ pneumoconiosis group was significantly higher than that of stage Ⅲ pneumoconiosis group (P<0.0125) . Conclusion: Patients with pneumoconiosis could experience a decline in right ventricular function at an early stage. The 3D-STI can accurately detect the GLS, GRS, GCS and hemodynamic changes of the right ventricular and evaluate the right ventricular function comprehensively and objectively. 3D-STI is of great significance for the early detection of right ventricular dysfunction in patients with pneumoconiosis.

Midazolam suppresses osteogenic differentiation of human bone marrow-derived mesenchymal stem cells.

OBJECTIVE: Previous study showed that peripheral-type benzodiazepine receptors (PBRs) are expressed in human mesenchymal stem cells (hMSCs) and diazepam was found to inhibit hMCSs viability in high concentration. Midazolam, a benzodiazepine derivative, is widely used as an intravenous sedative in hospital. Peripheral-type benzodiazepine receptors (PBRs) affect a broad spectrum of cellular functions. We tested the cell viability and osteogenic differentiation of hMSCs. PATIENTS AND METHODS: Bone marrow was collected from 12 patients during the operation of spine internal fixation. Cultivated with basal medium, the hBMSCs were incubated with or without midazolam (0.1, 1, 5, 10, 15, 20 µM, respectively). Cell viability were tested with MTS assay after 2, 4, 6 hours respectively. Cell morphology was observed and recorded at 6 hour. After cultivated with osteogentic medium, the hBMSCs were incubated with or without midazolam (5, 10, 15, 20 µM, respectively). Alkaline phosphatase (ALP) activity and alizarin red S staining were measured. Cultivated with osteogentic medium with or without treatment of 15 µM midazolam, the mRNA expression of ALP, type 1 collagen (COL1), Runx2 and PPARγ was analyzed by real-time RT-PCR. RESULTS: The treatments of midazolam inhibited cell viability to 85%-16% respectively (p < 0.05). Rounded up phenomenon with floating cells, Membrane-blebbed cells and cytoplasmic contraction were observed after 10, 15 or 20 µM midazolam treatment. The ALP activity and Calcium deposition of hBMSCs exposed to 15 and 20 µM midazolam was significantly inhibited at 7, 14 and 21 days (p < 0.05). And the mRNA expression of ALP, COL1 and PPARγ was significantly suppressed in the hBMSCs cultured with 15 µM midazolam (p < 0.05). CONCLUSIONS: Midazolam exert negative effect on cell viability and osteogenic differentiation of cultured hBMSCs. During sedation in critical care, the use of midazolam may suppress activity of hBMSCs.