Objective:To investigate the therapeutic effect of human umbilical cord mesenchymal stem cells (MSCs) on psoriasis-like mouse models induced by imiquimod and the underlying mechanisms.Methods:Eighteen C57BL/6 mice were randomly and equally divided into vaseline group, model group and treatment group according to a random number table. The mice in the model group and treatment group received topical treatment with 5% imiquimod cream at a dose of 62.5 mg once a day for 6 consecutive days on the shaved back, and those in the vaseline group received the treatment with the same amount of vaseline ointment; the mice in the treatment group were injected with 1.5×10 6 human umbilical cord MSCs via the caudal vein on days 1 and 4. The severity of skin lesions on the back of the mice was assessed everyday according to the psoriasis area and severity index (PASI) . Twenty-four hours after the last treatment, that is, on day 7, blood samples were taken, and the mice were sacrificed. The dorsal skin tissues were resected and subjected to hematoxylin and eosin (HE) staining. A single cell suspension of the resected spleen was prepared, and flow cytometry was performed to detect the Th1 and Th17 cell subsets in the spleen cells. Enzyme-linked immunosorbent assay was conducted to detect serum levels of cytokines interleukin (IL) -17A and tumor necrosis factor (TNF) -α. One-way analysis of variance was used for comparisons among groups, Tukey test for multiple comparisons, and repeated measures analysis of variance for the analysis of changes in the PASI score over time. Results:On day 7, there was obvious scaly erythema on the back of the mice in the model group, and the skin thickness and number of infiltrating inflammatory cells were significantly higher in the model group (78.73 ± 23.11 μm, 36.16 ± 2.95 cells/mm 2) than in the vaseline group (13.28 ± 4.57 μm, 13.33 ± 1.15 cells/mm 2, q=19.25, 7.21, respectively, both P < 0.001) . The treatment group showed significantly decreased PASI score, epidermal thickness and number of infiltrating inflammatory cells compared with the model group (all P < 0.001) . The percentage of Th17 cell subsets in the spleen cells and serum level of TNF-α were significantly lower in the treatment group than in the model group (both P < 0.05) . There were no significant differences in the spleen weight, spleen index, spleen cell count, Th1 cell percentage or serum IL-17A level between the treatment group and the model group (all P>0.05) . Conclusion:Human umbilical cord MSCs can effectively alleviate skin inflammation induced by imiquimod in the psoriasis-like mouse models, likely by inhibiting Th17 cell formation and TNF-α expression.

Objective:To investigatethe relationship between right ventricular blood flow components and right ventricular function in patients with pulmonary hypertension (PH) by 4D-FLOW cardiovascular MR (4D-FLOW CMR).Methods:Thirty patients with PH were prospectively enrolled in this study. All patients underwent right heart catheterization to measure hemodynamics and CMR to measure right ventricular blood flow and right ventricular function within 1 week. The long-axis 4-chamber and contiguous short axis cineslices were acquired with balanced steady-state free precession sequence to calculate RV functional metrics including right ventricular end diastolic volume, end systolic volume, ejection fraction, stroke output and other functional parameters. Ventricular flow was acquired in sagittal direction, using a 3D retrospectively ECG-triggered, navigator-gated prototype sequence to analyze.RV function and flow parameters were correlated with Spearman correlation analysis.Results:Right ventricular percent of direction flow(RVPDF),percent of delayed eject flow (RVPDEF),percent of retained flow (RVPRI) and percent of residual volume(RVPRV) of PH patients measured with 4D-FLOW were 16.4%±9.2%, 16.1%±5.6%, 16.8%±6.1%, and 50.5%±12.3%, respectively. RVPDF negatively correlated with RVPRVo ( r=-0.703, P<0.001) while RVPDEF positively correlated with RVPRI( r=0.955, P<0.001). RVPDF was positively correlated with right ventricular stroke volume index (RVSVI)( r=0.38, P=0.041) and right ventricular eject fraction(RVEF)( r=0.69, P<0.001), and negatively correlated with right ventricular end systolic volume index(RVESVI)( r=-0.65, P<0.001) and right ventricular mass index(RVMI)( r=-0.45, P=0.004). RVPRVo was negatively correlated with RVEF( r=-0.58, P=0.007). The sum of RVPDF and RVPDEF (RVPDF+RVPDEF) was 35.2%±11.4%. RVEF correlated with RVPDF+RVPDEF ( r=0.825, P<0.001) and comparable to RVPDF+RVPDEF ( t=1.427, P=0.164). RVPDF was negatively correlated with pulmonary vascular resistance (PVR) ( r=-0.52, P=0.007) while RVPRVo was positively correlated with PVR ( r=0.54, P=0.004). Conclusions:4D-FLOW CMR can be used to measure right ventricular ejection fraction in PH patients without respiratory control. In PH patients, the right ventricular direct blood flow was significantly decreased, while the residual blood flow was significantly increased. The right ventricular direct blood flow and residual blood flow were related to the right ventricular function and pulmonary vascular resistance, which were important parameters to evaluate the right ventricular function and afterload in PH.

OBJECTIVE To analyze the influential factors for rivaroxaban-induced bleeding events in patients with non- valvular atrial fibrillation （NVAF） and coronary heart disease. METHODS A total of 64 hospitalized patients with NVAF complicated with coronary heart disease who were treated with rivaroxaban and admitted to the Fuzhou University Affiliated Provincial Hospital from November 2021 to May 2023 were included in this retrospective study. The demographic data， laboratory test indexes and other general clinical data， and steady-state trough concentration of rivaroxaban were collected， and the dose- adjusted trough concentration was calculated. The occurrence of bleeding events within 6 months after discharge was recorded. The univariate analysis and binary Logistic regression analysis were adopted to determine the independent risk factors of rivaroxaban- related bleeding events. The binary Logistic regression equation was constructed to predict the probability of bleeding events. The area under the receiver operator characteristic （ROC） curve （AUC） was used to analyze the predictive value of the regression equation. RESULTS Among 64 patients， 19 patients had 24 case-times bleeding events， most of which were mild bleeding （19 case-times， 79.2%）， and mainly gastrointestinal bleeding （17 case-times， 70.8%）. After symptomatic treatment and adjustment of the anticoagulant regimen， most of them were improved or cured. In the univariate analysis， the proportion of patients with a history of anemia， platelet count， urea nitrogen content， steady-state trough concentration of rivaroxaban， dose-adjusted trough concentration and coagulation indexes [international normalized ratio， prothrombin time （PT）， activated partial thromboplastin time] in bleeding group were significantly more or higher than those in non-bleeding group， while the albumin level was significantly lower than that in non-bleeding group （P＜0.05）. In binary Logistics regression analysis， high PT level （odds ratio＝1.473， 95% confidence interval＝1.103-1.967， P＝ 0.009） and high rivaroxaban dose-adjusted trough concentration （odds ratio＝1.174， 95% confidence interval＝1.018-1.355， P＝ 0.027） were independent risk factors for rivaroxaban-related bleeding events. The binary Logistic regression equation of bleeding event prediction probability （P） was LogitP＝－6.975+0.387×PT level+0.161×dose-adjusted trough concentration， and the AUC of the ROC curve was 0.825 （95% confidence interval was 0.708-0.909， P＜0.001）. CONCLUSIONS The risk factors of rivaroxaban-related bleeding events in patients with NVAF and coronary heart disease include previous anemia history， high platelet count， high urea nitrogen content， high rivaroxaban steady-state trough concentration， high dose-adjusted trough concentration， high coagulation indexes and low albumin level. High PT level and high dose-adjusted trough concentration are independent risk factors that can be used to predict the risk of rivaroxaban-induced bleeding events. The regression equation has good predictive value.