BACKGROUND: Compared with the traditional organic fluorescent dyes, quantum dots present good biomarker characteristics. Especially, quantum dots for cell labeling and targeted bioimaging present unique optical properties.OBJECTIVE: To investigate the biocompatibility of CdSe/ZnS quantum dots with mononuclear macrophages.METHODS: The macrophages RAW264.7 were inoculated into 96-well plates containing 0, 50, 100 mg/L CdSe/ZnS quantum dots for 1 or 2 hours. Then, the fluorescent signal was detected by flow cytometry. After 0-24 hours of culture,the fluorescence signal intensity of the macrophages cultured with 50 mg/L CdSe/ZnS quantum dots was detected by flow cytometry. After 18 hours of culture, quantitative PCR was used to detect the levels of tumor necrosis factor α and interleukin 1β in macrophages, and macrophage proliferation cell apoptosis were detected by MTT and flow cytometry,respectively.RESULTS AND CONCLUSION: The fluorescence signal intensity was positively correlated with the mass concentration of CdSe/ZnS quantum dots, and the intensity of the fluorescent signal was increased with the labeling time. After labeling using 50 mg/L CdSe/ZnS quantum dots, the fluorescence signal of macrophages increased continuously with time, and reached the peak at 18 hours. Compared with 0 mg/L quantum dot group, 50, 100mg/L quantum dot groups could significantly promote the expression of tumor necrosis factor α and interleukin 1β in macrophages (P < 0.01 or P < 0.05).The level of tumor necrosis factor α in the 100 mg/L quantum dot group was higher than that in the 50 mg/L quantum dot group (P < 0.01). The expression of interleukin-1β showed no difference between 50 and 100 mg/L quantum dot groups.The cell proliferation in the 50 and 100 mg/L CdSe/ZnS quantum dot groups was significantly higher than that in the 0 mg/L quantum dot group (P < 0.05), but there was no difference between the former two groups. In addition, 50 and 100 mg/L CdSe/ZnS quantum dots had no significant effect on apoptosis of macrophages. To conclude, CdSe/ZnS quantum dots could activate macrophages and promote their proliferation and secretion of inflammatory factors, but did not affect their apoptosis.

Objective:To investigate the effect of butyrate produced by bacterial metabolism on immune features of murine bone marrow-derived dendritic cells(BMDCs) and its potential mechanisms.Methods: BMDCs were prepared from bone marrow cells of C57BL/6 mice by being cultured with GM-CSF and IL-4.The expression of CD80,CD86,B7-DC and MHCⅡ on BMDCs and its pri-ming ability on the proliferation of OVA257-264 antigen specific CD8+T cell were analyzed by using Flow cytometry.The mRNA levels of IL-6 and IL-12 in BMDCs were detected by real-time fluorescence quantitative PCR(q-PCR).Simultaneously,Griess reaction and Western blot was used for analyzing the levels of NO2-in BMDCs culture supernatant and the ERK phosphortylation in BMDCs respectivly.Results:Butyrate could decrease the levels of CD80,CD86,MHCⅡand B7-DC,and downregulate the capability of BMDCs in priming the proliferation of CD8+T cells.Furthermore,the secretions of IL-6,IL-12,NO2-and the phosphorylation of ERK were sup-pressed.Conclusion:Butyrate down-regulats the immune functions of BMDCs via inhibition of ERK phosphorylation in TLR 4 signaling pathway.

Objective: To evaluate the clinical characteristics and prognosis of patients with mitral valve prolapse (MVP). Methods: We retrospectively analyzed the clinical characteristics and prognosis of 148 MVP patients who underwent mitral valve surgery in Fuwai hospital from January 2012 to December 2015.The patients were divided into mucoid degeneration group (52 cases) and without mucoid degeneration group(19 cases) according to pathological examination of leaflets and chordate. Results: The clinical symptoms of MVP patients included dyspnea (59.5%(88/148)), chest distress and pain (52.7%(78/148)), and palpitations (36.5% (54/148)). Mitral valve repair was performed in 144 cases (97.3%), and mitral valve replacement was performed in 4 cases (2.7%). Posterior leaflet prolapse was the most common form of MVP (68.9%, 102/148). Pathological examination revealed myxomatous degeneration in 73.2% patients (52/71), fibrosis in 8.5% patients (6/71), and fibrinoid necrosis in 8.5% patients (6/71). Patients with mucoid degeneration had less atrial fibrillation before surgery (5.8%(3/52) vs. 42.1%(8/19), P<0.01), smaller preoperative left atrium diameter ((43.2±6.5) mm vs. (48.2±8.9) mm, P<0.05), more posterior leaflet prolapse (94.2%(49/52) vs. 63.2%(12/19), P<0.01), redundant chordae (26.9%(14/52) vs. 0, P<0.05) and leaflet thickening (76.9%(40/52) vs. 52.6%(10/19), P<0.05) when compared with patients without mucoid degeneration.Echocardiography examination at the postoperative follow-up of 39.0(22.3, 57.0) months revealed smaller left atrium diameter((38.5±7.1) mm vs. (45.3±8.3) mm, P<0.01), left ventricular end-diastolic diameter ((48.9±6.2) mm vs. (57.5±7.6) mm, P<0.01), reduced left ventricular ejection fraction ((61.2±7.1)% vs. (65.1±6.2)%, P<0.01) and less moderate or severe mitral regurgitation (1.4%(2/148) vs. 100.0%(148/148), P<0.01) compared with the corresponding preoperative values. Conclusions Dyspnea is the main symptom, and mucoid degeneration characterized by redundant chordae and leaflet thickening are the main pathological features of MVP patients.The surgical treatment of MVP patients is related with satisfactory outcome results.

Objective: To determine the value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) on predicting the long-term outcome of patients with hypertrophic cardiomyopathy (HCM) . Methods: NT-proBNP was measured in 831 consecutive patients with HCM at Fuwai Hospital from October 2009 to December 2013 and patients were followed up clinically for (53.3±15.4) months. Patients were divided into 3 groups according to NT-proBNP values: NT-proBNP<860 pmol/L (n=276) , 860 pmol/L≤NT-proBNP≤1 905 pmol/L (n=278) , NT-proBNP>1 905 pmol/L (n=277) . The related baseline data, laboratory examination and echocardiographic results were compared among groups. The primary endpoints of this study were all-cause mortality and cardiac transplantation. Cox proportional hazards model was used to estimate hazard ratio (HR) . Kaplan-Meier analysis was used to evaluate the survival status of patients among the 3 groups. Results: During a median follow-up of (53.3±15.4) months, all-cause mortality or cardiac transplantation occurred in 37 patients (4.5%) , event rate was 1.4% (4/276) , 4.0% (11/278) and 7.9% (22/277) in patients with NT-proBNP<860 pmol/L, 860 pmol/L≤NT-proBNP≤1 905 pmol/L and NT-proBNP>1 905 pmol/L, respectively. Multivariable Cox regression analysis identified that age (HR 1.066, 95%CI 1.027-1.107) and NT-proBNP (HR 1.026, 95% CI 1.010-1.042) were independent predictors of all-cause mortality or cardiac transplantation. Among the 3 groups, the survival rate of the NT-proBNP<860 pmol/L group was the highest,and that of the NT-proBNP>1 905 pmol/L group was the lowest (P<0.01) . Conclusions The level of NT-proBNP provides clinically relevant information for long-term adverse events risk stratification in patients with HCM.

Objective:To explore the surgical strategy of coronary artery bypass grafting(CABG) for moderate ischemic mitral regurgitation(IMR), and to clarify the impact of mitral valve surgical intervention(MVS) on the long-term prognosis of such patients.Methods:The clinical data of 234 consecutive patients with moderate IMR who received CABG from January 2013 to December 2018 were retrospectively included, with 184 males and 50 females. The age ranged from 29 to 78 years, with a mean of(61.5 ± 8.7) years old. According to whether MVS was performed at the same time, they were divided into CABG group(108 cases, CABG alone) and CABG+ MVS group(126 cases, CABG+ MVS at the same time). The long-term cardiac events, all-cause deaths, major cardiovascular and cerebrovascular adverse events(MACCE) and other end events were followed up. A matching queue was established by propensity matching score for statistical analysis.Results:After propensity matching score, a matching queue was established, including 78 pairs of patients. Survival analysis showed that the incidence of long-term cardiac events and postoperative new onset atrial fibrillation in CABG+ MVS group was significantly higher( P<0.05). However, there was no significant difference between the two groups in all-cause mortality, cardiogenic mortality, and the incidence of MACCE events( P>0.05). Cox regression analysis showed that simultaneous CABG+ MVS was a risk factor for long-term cardiac events and new postoperative atrial fibrillation. The results of subgroup studies showed that for patients without tricuspid regurgitation before operation, left ventricular end diastolic diameter>55 mm, and left ventricular ejection fraction(LVEF) ≤0.55, the probability of cardiac events after MVS at the same time of CABG was higher( P<0.05). However, patients with no tricuspid regurgitation before operation, left ventricular end diastolic diameter>55 mm, LVEF≤0.55, and left atrial diameter≥40 mm had a higher probability of atrial fibrillation after MVS at the same time of CABG( P<0.05). Conclusion:CABG can improve left ventricular remodeling in patients with moderate IMR, whether MVS intervention is performed at the same time or not, and the long-term survival rate of both is similar. CABG+ MVS in the same period can maintain a low residual reflux, but the incidence of long-term cardiac events and arrhythmias is high. The longer-term prognosis needs to be further studied. The surgical strategy of such patients should be selected individually according to the specific situation and the surgical quality in medical centers.

Objective To determine whether thyroid hormone (TH) level could also be an independent and incremental predictor of adverse events in patients with hypertrophic cardiomyopathy (HCM).Methods A total of 982 consecutive patients with HCM at the National Center for Cardiovascular Diseases (China) from October 2009 to December 2013 were included in the present study,and followed up till the end of December 2016.The patients were divided into three groups according to the levels of free triiodothyronine (FT3):the group 1 (FT3≤4.28 pmol/L,n=335),the group 2 (FT3＞4.28-＜4.79 pmol/L,n=310),and the group 3 (FT34.79-6.30 pmol/L,n=337).Results After a follow-up period of (53.8 ± 14.1) months,39 patients (4.0％) either suffered death with all causes or received a cardiac transplantation (7.8％,2.9％ and 1.2％ of the patients in the group 1,group 2 and group 3,respectively).A multivariable Cox regression analysis revealed that FT3≤4.28 pmol/L was associated with a significantly higher risk of all-cause mortality or cardiac transplantation (HR 8.83,95％ CI 1.115-69.905,P=0.039) in HCM patients.Conclusions Low levels of FT3 is a risk factor of adverse events for patients with HCM,indicting a role of FT3 as a marker for assessing the risk of long-term adverse events in these patients.