In various immunomodulatory systems,there exists a transmembrane receptor expressed on the surface of immune cells,which can play a role selectively,namely the sialic-binding immunoglobulin-like lectin(Siglec)family.Inhibition of host T cell antigen response is a key factor in inducing immune tolerance of liver transplantation.Recently,Siglec-15 has been found to be an important T cell suppressor molecule,and some of its family members have similar structure and biological characteristics.It is speculated that the mem-bers of Siglec family may be a new target for inducing liver immune tolerance.Therefore,this paper reviews the relevant literatures in this field,and takes Siglec-15 as the entry point to explore the possible role and mo-lecular mechanism of Siglec family in inhibiting host T cell antigen response and regulating immune response in order to provide the new ideas for the establishment of immune regulation and tolerance after transplanta-tion.

Objective:To assess the prognostic impact of frailty on elderly inpatients with heart failure.Methods:This prospective cohort study enrolled 121 in elderly patients with heart failure from Beijing Hospital, the General Hospital of the People's Liberation Army, and Beijing Tsinghua Changgung Hospital between September 2018 and April 2019.Patients were assessed for frailty using the Fried frailty phenotype and categorized into frail and non-frail groups.Follow-ups were conducted at 3-, 6-, and 12-months post-enrollment through clinic visits or phone calls to record adverse events.Composite endpoints include all-cause mortality and rehospitalization duo to deterioration of heart failure.Results:The study included 121 patients with an average age of 78.0±7.4 years, of whom 71(58.7%)were male and 57(47.1%)were classified as frail.Compared to the non-frail group, the frail group had lower estimated glomerular filtration rates[49.5±20.7 ml/(min·1.73m 2) vs.(64.0±27.1)ml/(min·1.73m 2)], lower scores in Basic Activities of Daily Living[5.0(4.0, 6.0) vs.6.0(5.0, 6.0)], Instrumental Activities of Daily Living[2.0(1.3, 7.8) vs.7.0(5.0, 8.0)], and Mini-Mental State Examination[26.0(16.0, 28.0) vs.27.0(22.3, 29.0)], all P<0.05.They also experienced longer hospital stays[10.5(6.0, 18.8)days vs.8.0(6.0, 11.8)days, P=0.008].During the follow-up period, the incidence of composite endpoint events was significantly higher in the frail group(43.9% vs.25.0%, P=0.029).Kaplan-Meier survival analysis demonstrated that the one-year incidence of composite endpoint events was significantly higher in the frail group( P=0.013).Multivariable Cox regression analysisindicated that frailty was an independent risk factor for composite endpoint events( HR=2.201, 95% CI: 1.089-4.447, P=0.028). Conclusions:Frailty is an independent risk factor for poor outcomes in elderly hospitalized patients with heart failure and should be considered a crucial factor in clinical assessment and treatment strategies.

Objective:To assess whether cardiac structure and function are associated with frailty in elderly inpatients.Methods:This was a cross-sectional study.Inpatients aged 65 years or over, admitted to Beijing Hospital, Chinese PLA General Hospital and Beijing Tsinghua Changgeng Hospital, were consecutively recruited from September 2018 to April 2019.A total of 925 elderly inpatients were enrolled in the study, including 285 frailty patients and 640 non-frailty patients.Frailty was assessed with the Fried frailty phenotype.Clinical and echocardiographic data were collected.The association of cardiac structure and function with frailty was analyzed.Results:Compared with the non-frailty group, the frailty group was older, had lower body mass index, and had higher rates of heart failure, atrial fibrillation/atrial flutter, history of stroke/transient ischemic attack, renal insufficiency, and history of falls.N-terminal B-type natriuretic peptide(NT-proBNP)levels were higher while creatinine clearance and hemoglobin levels were lower(all P<0.05); The frailty group had a larger anterior-posterior left atrial diameter[(37.8±7.1)mm vs.(36.3±5.1)mm, t=-3.134, P=0.002]and a higher proportion with the left atrial anterior posterior diameter ≥45 mm[15.8%(45/285) vs.6.1%(39/640), χ2=22.452, P<0.001], a lower left ventricular ejection fraction[(60.1±9.5)% vs.(61.9±7.5)%, t=2.817, P=0.005]and a faster peak mitral inflow velocity[(0.8±0.3)cm/s vs.(0.7±0.2)cm/s, t=-2.675, P=0.003]. Multivariate logistic regression analysis showed that the left atrial anterior posterior diameter ≥45 mm was an independent correlation factor for frailty( OR=2.249, P=0.015). Increased age( OR=1.099, P<0.001), heart failure( OR=1.786, P=0.049), history of stroke/transient ischemic attack( OR=1.960, P=0.001)and decreased hemoglobin( OR=0.984, P=0.008)were independently associated with frailty. Conclusions:The left atrial anterior posterior diameter ≥45 mm and heart failure were independently associated with frailty.Assessing cardiac structure and function and screening for cardiovascular diseases in frailty patients should be emphasized.

Objective:To analyze the clinical characteristics and prognostic factors in patients with new-onset acute heart failure (AHF) and acutely decompensated chronic heart failure (ADCHF).Methods:Patients with heart failure (HF) admitted to Beijing Hospital during January 2009 to December 2017 with follow-up records were retrospectively enrolled. According to the duration of heart failure, the patients were divided into new-onset AHF group (duration of HF<1 month) and ADCHF group (duration of HF ≥1 month). Clinical data were collected and endpoint events (all-cause death and cardiovascular death) were recorded. The Kaplan-Meier survival curve and the log-rank method was used to compare survival between different groups. The multivariate Cox regression model was used to analyze the independent risk factors for the end-point events in patients with new-onset AHF and ADCHF.Results:The study enrolled 562 patients,292 (52.0%) with new-onset AHF and 270 (48.0%) with ADCHF. Patients with new-onset AHF were more likely to have coronary heart disease, acute myocardial infarction, higher diastolic blood pressure and higher troponin I levels(χ2=12.999,15.018, t=-2.088, Z=-2.727; all P<0.05). Patients with ADCHF were more likely to have poor cardiac function, atrial fibrillation, larger left ventricle and left atrium diameter, higher proportion of patients with pulmonary hypertension(χ2=16.565, 15.688, t=2.714, 5.029, χ2=15.274; all P<0.05). There were 205 (36.5%) all-cause deaths and 132 (23.5%) cardiovascular deaths during 28 (14, 60) months of follow-up. All-cause mortality rate [33.2%(97/292) vs. 40.0%(108/270), log-rank P=0.010] and cardiovascular mortality rate [18.8%(55/292) vs. 28.5%(77/270), log-rank P=0.001]were significantly lower in patients with new-onset AHF than those in ADCHF group. Multivariate Cox regression analysis showed that low body mass index (BMI), reduced hemoglobin, reduced resting heart rate, enlarged left atrium, and segmental wall motion abnormalities were independent risk factors for poor prognosis in new-onset AHF patients. It was different with ADCHF patients. Conclusion:Patients with new-onset AHF are more likely to have coronary heart disease; and lower BMI, reduced hemoglobin, acute coronary disease are associated with poor prognosis of patients. It is necessary to identify the underlying diseases early and actively standardize treatment to avoid the deterioration of cardiac function and readmission.

Objective To characterize autopsy pathological changes of the coronary artery and left ventricular myocardium in elderly patients with moderate to severe calcified aortic stenosis,and to analyze the causes of death.Methods Seventeen cases of moderate to severe calcified aortic stenosis were identified from an autopsy database of Beijing Hospital containing 909 elderly patients(aged from 60-100 years)collected from April 1,1969 to October 31,2013.All cases were confirmed by autopsy and were analyzed retrospectively.The characteristics of coronary artery lesions,myocardial pathological changes and causes of death were summarized.Results Aortic stenosis was detected in 1.1％(2/190),1.9％(5/266),3.7％(11/297)and 6.4％(10/156)of patients in the 60-69,70-79,80-89 and 90-100 age groups,increasingly prevalent with age(x2=10.08,P=0.018).In addition,seventeencases were confirmed to have moderate to severe calcified aortic stenosis.Of these cases,13 (76.5％) had coronary artery disease and 5 (29.4 ％)had severe coronary stenosis.The left anterior descending (LAD) artery was most commonly involved(47.0 ％).No thrombus was found in the coronary arteries,and only one had chronic total occlusion(5.9 ％).Myocardial infarction was confirmed in all 13 patients with coronary artery disease,including six cases(35.3％)of AMI,11 cases(64.7 ％)of OMI and four cases (23.5 ％)of AMI and OMI.Among AMI cases,transmural infarction was shown only in one case,with two cases of non-transmural infarction,two cases of subendocardial infarction and one case of focal myocardial infarction.Among OMI cases,transmural infarction was shown in one case,with two cases of non-transmural infarction,four cases of subendocardial infarction and four cases of focal myocardial infarction.The clinical misdiagnosis rate of OMI was as high as 81.8％.Patients died mainly from cardiovascular disease(70.6 ％),with six cases (35.3 ％) from myocardial infarction,three from heart failure(17.6％) and three from malignant arrhythmia (17.6 ％).Six of the cases suffered from sudden cardiac death(35.3％)with biopsy-confirmed myocardial infarction changes.Conclusions The incidence of CAD in elderly patients with calcific aortic stenosis is high.Pathological changes of myocardial infarction,especially of subendocardial and focal infarction,occur in patients with moderate to severe aortic stenosis and coronary heart disease with a high clinical misdiagnosis rate.Aortic stenosis implicates both the valve and myocardium.Assessment of myocardial lesions in patients with calcific aortic stenosis should be carefully conducted in clinical practice.

Objective To summarize the prevalence of diseases and main causes of death in elderly patients aged 80 and over,and to provide epidemiological evidence for preventive care of geriatric diseases.Methods A total of 922 autopsy cases aged from 60 to 106 at our hospital from April 1,1969 to October 31,2013 were analyzed.The disease spectrum and the main causes of death in cases aged 80 and over were compared with those in cases aged from 60 to 79.Results The top fifteen pathological diagnoscs in elderly patients aged 80 and over were chronic pyelonephritis(62.2 ％,290 cases),coronary heart disease(59.2％,276 cases),bronchopneumonia(52.6％,245 cases),prostatic hyperplasia (58.1％,232/399),pleural effusion (47.9％,223 cases),malignant tumor (47.4 ％,221 cases),chronic bronchitis(43.1 ％,201 cases),pulmonary congestion or edema(42.1 ％,196 cases),pericardial effusion (41.8 ％,195 cases),old myocardial infarction (40.1 ％,187 cases),emphysema (36.3％,169 cases),chronic cystitis (22.7％,106 cases),gallstones or cholecystitis (14.2％,66 cases),acute myocardial infarction (13.7％,64 cases),and gastrointestinal bleeding (12.4 ％,58 cases).The leading causes of death were malignant tumor (47.4 ％,221 cases),infectious disease(26.6％,124 cases)with pneumonia as the most prevalent type(24.0％,112 cases),and cardiovascular disease (myocardial infraction and heart failure) (24.7％,115 cases).Conclusions The most prevalent diseases in patients aged 80 and over are chronic pyelonephritis,coronary heart disease,bronchopneumonia,and malignant tumor.The top three causes of death in the aged are malignant tumor,cardiovascular disease.and pneumonia.Enhanced screening and management of the above diseases for inpatients aged 80 and over are recommended.

Objective: To analyze the cardiac pathological features of elderly coronary artery disease (CAD) patients (60 years and over) and evaluate the pathological features at autopsy and risk factors of patients with acute myocardial infarction (AMI). Methods: Data from 471 elderly patients (aged from 60 to 100 years old) with CAD confirmed by autopsy hospitalized in our hospital from April 1969 to October 2013 were retrospectively reviewed. Patients were divided into 2 groups: AMI group(n=128) with AMI as the primary cause of death and the rest served as control group(n=343). The pathological features of coronary lesion and related risk factors of AMI were analyzed. Results: In patients aged 60 and over with CAD, 48.8%(230/471) had severe coronary stenosis, 18.7%(88/471) had three-vessel disease, 71.8% cases (338/471) had left anterior descending artery(LAD)grade Ⅲ and over stenosis, 29.9% (141/471) had LAD grade Ⅳ stenosis, 25.9%(122/471) had left main coronary artery(LM) grade Ⅲ and over stenosis, 9.6%(45/471) had LM grade Ⅳ stenosis, 27.1%(128/471) had AMI. The first AMI accounts for 39.1%(50/128), and 60.9%(78/128) had both AMI and old MI. Compared with the control group, AMI group were younger ((77.1±11.6) years vs. (83.2±9.1) years, P<0.01), had more severe coronary artery stenosis lesion (77.3%(99/128) vs. 38.2%(131/343), P<0.01), higher coronary index which reflects the overall arteriosclerosis (9.9±2.8 vs. 8.0±2.5, P<0.01), more three-vessel disease (30.3%(43/128) vs. 13.7%(45/343), P<0.01), heavier heart weight ((447.8±90.6)g vs. (426.6±99.1)g, P<0.05), higher prevlence of pulmonary congestion or edema (57.8%(74/128) vs. 39.9%(137/343), P<0.01). Twenty-three cardiac ruptures (23/128, 18.0%) were observed in AMI group. Logistic regression analysis showed that grade Ⅳ LAD stenosis (OR=3.55, 95%CI 2.05-6.17, P<0.01), three-vessel disease(OR=2.47, 95%CI 1.30-4.67, P<0.01) were the independent risk factors of AMI in elderly patients with CAD. Conclusions Severe coronary stenosis is common in CAD patients aged 60 and over. Patients aged 60 and over with AMI have more severe coronary artery stenosis lesion and heavier heart weight. Cardiac rupture is not uncommon in elderly patients with AMI. Severe LAD stenosis and three-vessel disease are the independent risk factors of AMI in the elderly.

Objective: To analyze the pathological feathers of the heart in elderly (60-99 years old) heart failure patients with preserved ejection fraction (HFpEF) and coronary artery disease (CAD) and to explore the misdiagnosis and missed diagnosis rates. Method: This retrospective study included 154 HFpEF (left ventricular ejection fraction (LVEF)≥50%) cases and 49 heart failure with reduced ejection fraction (HFrEF) (LVEF≤40%) cases aged 60-99 years old out of 1 485 consecutive autopsy cases. Pathological changes of the heart and coronary artery were compared between patients with HFpEF and HFrEF. The misdiagnosis and missed diagnosis rates of HFpEF were analyzed based on pathological examination. Results: Patients with HFpEF were older than those with HFrEF ((85.7±7.4) vs. (82.9±7.8) years old, P=0.017). Among all the cases, CAD was diagnosed in 105 (68.2%) HFpEF patients and 38 (77.6%) HFrEF patients. Compared with patients with HFrEF, HFpEF patients displayed less acute myocardial infarction (12.3%(19/154) vs. 59.2%(29/49), P<0.01) and more chronic myocardial ischemia (18.2%(28/154) vs. 6.1%(3/49), P=0.041). 51.9% (80/154) HFpEF and 71.4% (35/49) HFrEF patients (P=0.017) displayed >50% left anterior descending artery stenosis. Prevalence of >75% coronary arterial stenosis (51% (25/49) vs. 20.1%(31/154), P<0.001) and more than one vessel lesions (55.1%(27/49) vs. 33.8%(52/154), P=0.008) were significantly higher in HFrEF patients than in HFpEF patients. The misdiagnosis rate of CAD in HFpEF was 63.3% (31/49). Among HFpEF, the missed diagnosis rate of acute myocardial infarction was 57.9% (11/19) and the missed diagnosis rate of old myocardial infarction was 57.7% (45/78). Conclusions CAD and chronic myocardial ischemia are common in elderly patients with HFpEF. Chronic myocardial ischemia may play an important role in the development of HFpEF of elderly CAD patients. Among HFpEF patients, the misdiagnosis rate of CAD and missed diagnosis rate of myocardial infarction are high, so the accurate evaluation of myocardial ischemia status is of great importance.