Soluble CD40 ligand, platelet surface CD40 ligand, and total platelet CD40 ligand in atrial fibrillation: relationship to soluble P-selectin, stroke risk factors, and risk factor intervention

BACKGROUND: Abnormal levels of soluble CD40 ligand (sCD40L) have been reported in patients with hypertension, coronary artery disease, diabetes mellitus, heart failure, and stroke, all of which are conditions that are associated with nonvalvular atrial fibrillation (AF). We hypothesized the following: (1) CD40 ligand (CD40L)-related indexes (ie, platelet surface expressed CD40L, the soluble fragment of CD40L [sCD40L], and the total amount of CD40L per platelet [pCD40L]) are elevated in patients with AF compared to control subjects; (2) these indexes correlate with soluble P-selectin (sP-selectin), which is an established platelet marker; and (3) these indexes differentiate "high-risk" from "low-risk" subjects. METHODS: We performed a case-control study of 121 AF patients, 71 "disease control subjects," and 56 "healthy control subjects." Peripheral venous levels of platelet surface-expressed CD40L were analyzed by flow cytometry, while levels of sCD40L, pCD40L, and sP-selectin were measured by enzyme-linked immunosorbent assay. RESULTS: AF patients had significantly higher sCD40L levels compared to healthy control subjects (p = 0.042), with no difference in platelet surface CD40L and pCD40L levels. A positive correlation was noted between levels of sCD40L and pCD40L, and not with sP-selectin. CD40L-related indexes failed to distinguish between high-risk and low-risk AF patients. AF patients receiving optimal antithrombotic therapy had significantly lower pCD40L levels (p < 0.001) compared to control subjects. Optimized AF management also resulted in significant reductions in the levels of sCD40L (p = 0.023) and pCD40L (p < 0.001). CONCLUSION: CD40L-related indexes are not useful in the risk stratification of AF patients, and abnormal sCD40L levels can be reduced by intense multifactorial risk management. While there is a significant, albeit modest, excess of platelet activation in AF patients (as measured by sCD40L levels) compared to healthy control subjects, this is not in excess of that seen in patients with underlying cardiovascular diseases.     

Elevated platelet microparticle levels in nonvalvular atrial fibrillation: relationship to p-selectin and antithrombotic therapy

BACKGROUND: Platelet microparticles (PMPs), are procoagulant membrane vesicles that are derived from activated platelets, the levels of which are elevated in patients with hypertension, coronary artery disease (CAD), diabetes, and stroke, all of which are conditions that lead to (and are associated with) atrial fibrillation (AF). We hypothesized the following: (1) PMP levels are elevated in patients with AF compared to levels in both healthy control subjects (ie, patients without cardiovascular diseases who are in sinus rhythm) and disease control subjects (ie, patients with hypertension, CAD, diabetes or stroke, but who are in sinus rhythm); (2) PMP levels correlate with levels of soluble P-selectin (sP-selectin) [a marker of platelet activation]; and (3) PMP levels are related to the underlying factors in patients with AF that contribute to the overall risk of stroke secondary to AF. METHODS: We performed a case-control study of 70 AF patients, 46 disease control subjects and 33 healthy control subjects. Peripheral venous levels of PMP and sP-selectin were analyzed by flow cytometry and enzyme-linked immunosorbent assay, respectively. RESULTS: Both AF patients and disease control subjects had significantly higher levels of PMPs (p < 0.001) and sP-selectin (p = 0.001) compared to healthy control subjects, but there was no difference between AF patients and disease control subjects. There was no difference in PMP levels between patients with paroxysmal and permanent AF (p = 0.581), and between those receiving therapy with aspirin and warfarin (p = 0.779). No significant correlation was observed between PMP and sP-selectin levels (p = 0.463), and the clinical characteristics that contribute to increased stroke risk in patients with AF. On stepwise multiple regression analysis in the combined cohort of AF patients plus disease control subjects, the presence/absence of AF was not an independent determinant of PMP and sP-selectin levels. CONCLUSION: There is evidence of platelet activation (ie, high PMP and sP-selectin levels) in AF patients, but this is likely to be due to underlying cardiovascular diseases rather than the arrhythmia per se.     

Enhanced P-selectin expression and increased soluble CD40 Ligand in patients with Type 1 diabetes mellitus and microangiopathy: evidence for platelet hyperactivity and chronic inflammation

Aims/hypothesis Platelet activation, endothelial dysfunction and inflammation may be involved in early stages of diabetic microangiopathy. We therefore investigated patients with Type 1 diabetes mellitus, without (n=19) and with (n=20) microangiopathy, matched for glycaemic control and duration of disease, and matched with healthy control subjects (n=27).Methods Platelet activation was measured as platelet P-selectin expression using whole blood flow cytometry and as soluble P-selectin by immunoassay. Von Willebrand factor antigen in plasma, serum soluble E-selectin, CD40 ligand (sCD40L) and C-reactive protein (CRP) served as markers for endothelial function and inflammation.Results Thrombin-induced platelet P-selectin expression was enhanced, and soluble P-selectin and sCD40L concentrations were increased in patients with microangiopathy compared with the control subjects (p<0.01 for both) and with patients without microangiopathy (p<0.05 for P-selectin expression and sP-selectin), whereas all three parameters were similar in patients without microangiopathy and in the control subjects. CRP and soluble E-selectin were increased in patients with microangiopathy, compared with the control subjects (p<0.01 and p<0.05), whereas von Willebrand factor did not differ between the groups.Conclusions/interpretation Microangiopathy in Type 1 diabetes is associated with platelet hyperactivity, endothelial dysfunction and low-grade inflammation, indicating an increased risk for cardiovascular disease.Abbreviations sP-selectin Soluble P-selectin - sCD40L soluble CD40 Ligand - CRP C-reactive protein     

Elevated platelet P-selectin expression and platelet activation in high risk patients with uncontrolled severe hypertension

BACKGROUND: Uncontrolled severe hypertension is associated with alarming rates of cardiovascular events but the mechanisms of vascular injury are not well understood. Recent investigative interest has focused on platelet activation and platelet P-selectin (CD62P) as direct mediators of vascular inflammation and injury. We investigated the association of extreme blood pressure (BP) elevation with platelet P-selectin and fibrinolytic markers in high risk patients with severe hypertension. METHODS: Cross-sectional comparison of platelet CD62, tissue plasminogen activator antigen (tPA), and plasminogen activator inhibitor-1 activity (PAI-1) among 3 BP groups: untreated severely hypertensive patients (SHT; n=18), untreated mildly hypertensive patients (MHT; n=19), and normotensive controls (NT; n=16). RESULTS: Platelet CD62 was greatest in SHT (p=0.00008) and showed a strong correlation with both systolic (p=0.0002, r=0.52) and diastolic (p=0.0003, r=0.52) BP. tPA was greater in SHT than MHT or NT (ANOVA; p=0.02) and correlated with diastolic BP but not SBP. PAI-1 did not correlate with either SBP or DBP but was related to body mass index, diabetes, and dyslipidemia. CONCLUSIONS: Platelet CD62 demonstrated a strong and graded association with both systolic and diastolic BP that persisted in the presence of multiple concomitant risk factors. The association of BP with CD62P was stronger than with either PAI-1 or tPA-Ag. Platelet activation and platelet CD62 increase in a BP-dependent manner and this relationship persists at extreme levels of BP. Platelet activation and platelet CD62 may participate in the accelerated target organ injury observed in high risk patients with severe hypertension.     

Increased platelet activation in young patients with prehypertension

Mean platelet volume (MPV) and sP-selectin levels are considered as indicators of platelet activation. In this study, we assessed platelet activation in prehypertensive patients by comparing MPV and sP-selectin levels of these patients with healthy conrols. The study population consisted of 25 newly diagnosed prehypertensive individuals (18 men, mean age = 34 ± 6 y) and 25 healthy control subjects (16 men, mean age = 33 ± 6 y) eligible for the current study. Blood pressure (BP) , lipid profile, plasma glucose, HOMA-IR values, sP-selectin levels, platelet counts, and MPV were measured in both groups. Other than systolic blood pressure (SBP) and diastolic blood pressure (DBP), baseline demographic characteristics of both groups were similar. No significant difference was found between the platelet counts of the two groups. Despite comparable platelet counts, platelet activation parameters were found significantly higher in the prehypertensives. Prehypertensives had larger a MPV value compared to that of the control group (8.24 ± 0.46 fl vs. 7.70 ± 0.64 fl; P = 0.001) and plasma sP-selectin levels were also significantly higher in the prehypertensive patients (163.60 ± 41.21 ng/ml vs. 132.80 ± 36.46; P = 0.007). Spearman correlation analysis revealed moderate positive correlation between SBP and platelet activation parameters (for SBP and MPV, r = 0.60, p = 0.001; for SBP and sP-selectin r = 0.51, p = 0.009). Prehypertension causes platelet activation as evidenced by increased MPV and plasma sP-selectin levels. Increased platelet activation might be related to increased vascular thrombotic risk in those patients.     

Increased platelet activation in subjects chronically exposed to cadmium: A pilot study

Cadmium exposure has been reported to be associated with the risk of vascular disorders. Here, we investigated platelet activity in subjects with chronic cadmium exposure. Eighteen and 15 women participated in this study as chronically cadmium-exposed and control non-exposed subjects, respectively. Plasma P-selectin and CD40 ligand (CD40L), soluble markers of platelet activation, were measured. Platelet aggregation in whole blood, P-selectin and activated glycoprotein (aGP) IIb/IIIa expression on platelets and platelet–leukocyte aggregates were determined. The levels of plasma P-selectin and CD40L increased in subjects with chronic cadmium exposure compared with control subjects. Platelet aggregation induced by adenosine diphosphate (ADP) was higher in cadmium-exposed subjects than control subjects. Cadmium-exposed subjects had higher baseline and ADP-induced aGPIIb/IIIa expression on platelets than control subjects. Platelet–neutrophil aggregates also increased in cadmium-exposed subjects. Blood cadmium correlated with ADP-induced aggregation, aGPIIb/IIIa expression and platelet–neutrophil aggregates, while urinary cadmium correlated with soluble P-selectin. However, cadmium only at high concentration (15?µM) could potentiate ADP-induced platelet activation in vitro. In conclusion, our pilot data show that cadmium-exposed subjects have increased baseline platelet activation and reactivity.     

Increased mean platelet volume in primary Raynaud's phenomenon

We hypothesized that mean platelet volume (MPV), a reliable marker of platelet activation, might be elevated in primary Raynaud's phenomenon (PRP) even if there was no thrombotic complication in our subjects. In this retrospective-cohort study, we examined the clinical value of MPV in 200 patients with PRP and 116 clinical controls, and measured MPV and platelet P-selectin (CD62P) in all study participants. We also evaluated the effect of age, gender, and disease duration on these platelet activation markers in PRP. MPV and CD62 positivities were significantly (p<0.001) elevated in patients with PRP compared with controls. These differences retained when patients and controls were analyzed according to age, gender, and the disease duration. In logistic regression analysis, MPV (OR: 15.8, 95% CI: 8.14-30.64, p<0.001) and CD62P (OR: 11.3, 95% CI: 4.85-26.12, p<0.001) were found to be independently associated with PRP. In conclusion, increased MPV is independently related to PRP, and its level was not influenced by age, gender, and the duration of PRP.     

Effects of efonidipine on platelet and monocyte activation markers in hypertensive patients with and without type 2 diabetes mellitus

We compared the levels of microparticles, platelet activation markers, soluble cell adhesion molecules, and soluble selectins between hypertensive patients with and without type 2 diabetes and control subjects. Binding of anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib monoclonal antibodies to platelets did not differ significantly between the hypertensive patients and controls, but platelet expression of activation markers (CD62P, CD63, PAC-1, and annexin V) was higher in the hypertensive patients. Platelet-derived microparticle (PDMP) and monocyte-derived microparticle (MDMP) levels were significantly higher in the hypertensive patients than in the controls. Soluble ICAM-1, VCAM-1, P-selectin, and E-selectin levels were also higher in the hypertensive patients, and they were significantly higher in the hypertensive patients with diabetes. After treatment with efonidipine, the levels of PDMPs, CD62P-, CD63-, PAC-1-, and annexin V-positive platelets, sICAM-1, sVCAM-1, sP-selectin, and sE-selectin all decreased significantly. The MDMP levels decreased, and the decrease was significant in the hypertensive patients with diabetes. These findings suggest that administration of efonidipine to hypertension patients with diabetes may prevent the development of cardiovascular complications caused by cell adhesion molecules or activated platelets and monocytes.     

The mean platelet volume in subjects with impaired fasting glucose

Mean platelet volume (MPV), a determinant of platelet function, is a newly emerging risk factor for atherothrombosis. Impaired fasting glucose (IFG) is probably a frequent glycemic disorder in the general population and is considered as a prediabetic state. The present study was designed to evaluate MPV in subjects with IFG compared with diabetic patients and normoglycemic control subjects. We selected 50 patients with type 2 diabetes mellitus, 50 subjects with IFG, and 50 normoglycemic healthy subjects matched for age, gender, and body mass index. MPV was very significantly higher in diabetic and IFG groups than in control group (p < 0.00, p < 0.05, respectively); it was also higher in diabetic group than in IFG group (p < 0.05). Platelet counts were not different among the study groups (p > 0.05). Platelet mass was significantly higher in diabetic and IFG groups than in normotensives (p < 0.00, p < 0.05, respectively); and it was also higher in diabetic group than in IFG group (p < 0.05). MPV and platelet mass were positively correlated with fasting glucose and HbA1c in diabetic and IFG groups (p < 0.05). In conclusion, our data suggests one possible mechanism by which subjects with IFG may be at increased cardiovascular risk.     

Plasma adenosine levels and platelet activation in patients with atrial fibrillation

Platelet activation is observed in patients with atrial fibrillation (AF). P-selectin, which is expressed on platelet activation, plays an important role in the formation of thromboemobli. Because adenosine is known to attenuate platelet activation, we evaluated adenosine levels and 2 indicators of platelet activation, i.e., expression of P-selectin on platelets and plasma levels of beta-thromboglobulin, in 28 patients with AF (20 men and 8 women, age range 64+/-2 years) with sex- and age-matched (+/-2 years) subjects with sinus rhythm. The incidence of risk factors for stroke except for coronary heart disease and in echocardiographic parameters did not differ between the 2 groups. Plasma adenosine levels were lower (p <0.05) in patients with AF than in controls (mean [interquartile range] 13.4 [19.3-9.3] vs 19.1 [30.8-11.9] nmol/L). The expression of P-selectin on platelets (6.8% [13.6-3.4] vs 4.0% [8.8-1.8]) and plasma levels of beta-thromboglobulin were higher (p <0.05) in patients with AF. Flow cytometric analysis revealed that an antagonist of adenosine receptors, 8-sulfophenyltheophylline, increased the expression of P-selectin on platelets in a dose-dependent manner in the in vitro study. These results suggest that decreased plasma levels of adenosine were associated with platelet activation in patients with AF. Substitution of adenosine may provide a strategy for preventing platelet activation in these patients.     

Increased mean platelet volume in primary Raynaud's phenomenon

We hypothesized that mean platelet volume (MPV), a reliable marker of platelet activation, might be elevated in primary Raynaud's phenomenon (PRP) even if there was no thrombotic complication in our subjects. In this retrospective-cohort study, we examined the clinical value of MPV in 200 patients with PRP and 116 clinical controls, and measured MPV and platelet P-selectin (CD62P) in all study participants. We also evaluated the effect of age, gender, and disease duration on these platelet activation markers in PRP. MPV and CD62 positivities were significantly (p?<?0.001) elevated in patients with PRP compared with controls. These differences retained when patients and controls were analyzed according to age, gender, and the disease duration. In logistic regression analysis, MPV (OR: 15.8, 95% CI: 8.14–30.64, p?<?0.001) and CD62P (OR: 11.3, 95% CI: 4.85–26.12, p?<?0.001) were found to be independently associated with PRP. In conclusion, increased MPV is independently related to PRP, and its level was not influenced by age, gender, and the duration of PRP.     

Low-grade endotoxemia,gut permeability and platelet activation in patients with impaired fasting glucose

Background and aim

Impaired fasting glucose (IFG) is associated with an increased risk of cardiovascular disease but the underlying mechanisms are still unclear. Aim of the study was to investigate the interplay between platelet activation, lipopolysaccharides (LPS) and markers of oxidative stress in patients with IFG and control subjects.

Increased circulating platelet–leucocyte complexes and platelet activation in patients with antiphospholipid syndrome, systemic lupus erythematosus and rheumatoid arthritis

It is possible that platelet activation may play a pathogenic role in the increased risk of thrombosis associated with antiphospholipid antibodies (APA). In this study, levels of in vivo platelet activation were measured in 20 patients with primary antiphospholipid syndrome (PAPS) and 30 systemic lupus erythematosus (SLE) patients (14 of whom had secondary APS) using sensitive flow cytometry. Soluble P-selectin levels were also assayed. Platelet CD63 expression was significantly higher in PAPS than normal controls (P = 0.007), as well as SLE patients with and without secondary APS (P = 0.03 and P = 0.002 respectively). PAC-1 binding was significantly higher in PAPS than the control group (P = 0.007) and SLE patients without APS (P = 0.015). Platelet-leucocyte complexes were significantly higher in SLE patients than both PAPS and the control group, and platelet-monocyte complexes were significantly increased in PAPS compared with the control group. (Platelet-leucocyte complexes were also significantly higher than controls in 10 rheumatoid arthritis (RA) patients without APA). Soluble P-selectin levels were significantly higher in PAPS and SLE patients than the control group. Platelet CD62p expression, annexin V binding and platelet microparticle numbers were not increased in PAPS or SLE patients. We conclude that there is evidence of increased platelet activation in PAPS and SLE, and this is important to note as it may have potential therapeutic implications with respect to use of antiplatelet agents in these patients.     

流式细胞术分析活化血小板及其在急性肺血栓栓塞症中的临床意义

目的应用全血流式细胞术(FCM)结合血小板活化特异性单抗检测急性肺血栓栓塞症(PTE)患者血小板活化状态,探讨血小板活化在急性PTE中的作用及临床意义.方法以凝血因子I受体(FIB-R)、P-选择素(CD62P)作为分子标志物,利用FCM荧光标记法检测36例急性PTE患者和20例健康对照者微量全血FIB-R、CD62P血小板表面阳性表达的百分率,并比较急性PTE患者治疗前后FIB-R、CD62P在血小板表面阳性表达的变化.结果急性PTE患者血小板表面活性标志蛋白FIB-R、CD62P阳性率分别为(18.30±12.23)%、(12.07±6.54)%,均显著高于对照组[(1.81±0.88)%、(2.18±1.50)%,(P＜0.01)].溶栓和抗凝治疗后各项指标均较治疗前明显下降(均P＜0.01).结论急性PTE患者体内存在着明显的血小板活性增强,全血FCM能准确地反映体内血小板的活化水平.     

Effects of eicosapentaenoic acid on platelet activation markers and cell adhesion molecules in hyperlipidemic patients with Type 2 diabetes mellitus

We compared the levels of microparticles, platelet activation markers, soluble cell adhesion molecules, soluble selectins, and antioxidized low-density lipoprotein (anti-Ox LDL) antibody between patients with hyperlipidemia and control subjects. Binding of anti-glycoprotein (GP) IIb/IIIa and anti-GPIb monoclonal antibodies to platelets did not differ significantly between the hyperlipidemic patients and controls. However, expression of activation markers (CD62P, CD63, PAC-1, and annexin V) by platelets was higher in the hyperlipidemic patients with Type 2 diabetes. The levels of platelet-derived microparticles (PDMPs) and monocyte-derived microparticles (MDMPs) were significantly different in hyperlipidemic patients with Type 2 diabetes and controls. Soluble P-selectin (sP-selectin), soluble E-selectin (sE-selectin), and anti-Ox LDL antibody also showed higher levels in the hyperlipidemic patients with Type 2 diabetes. After treatment with eicosapentaenoic acid (EPA), the levels of CD62P, CD63, annexin V, PDMPs, and MDMPs, sE-selectin, and oxidized LDL antibody were reduced significantly. Triglyceride (TG) and total cholesterol levels were also decreased. Anti-Ox LDL antibodies and MDMPs were correlated positively with platelet CD62P (plt-CD62P) levels. These findings suggest that in hyperlipidemic patients with Type 2 diabetes, EPA may prevent complications caused by oxidized LDL, E-selectin, and activated platelets or monocytes.     

Does renal carcinoma affect the expression of P-selectin on platelets?

We studied changes in the expression of P-selectin on the blood platelet plasma membrane. The aim of the study was to determine the influence of renal carcinoma on P-selectin expression associated with changes in platelet morphology. Venous blood was collected from 30 patients with renal carcinoma and from 24 control subjects for cytometric analysis and to evaluate platelet morphology. P-selectin being the CD62P receptor on blood platelets was marked by anti-CD61/62P MoAb, and the results were presented as the percentage of CD62P-positive cells. Changes in the expression of the CD62P on the platelet plasma membrane during activation were investigated by flow cytometry in a comparative study of in vivo activation and in vitro platelet reactivity. Platelet activation reflected by P-selectin expression was higher in the group of patients (4.45 +/-1.96), compared to control (2.48 +/-1.66) (p < 0.05). However, adenosine diphosphate [ADP] -stimulated platelet reactivity in renal cancer patients increased only by 0.24% (p > 0.05), while following activation by thrombin by 0.54% (p < 0.05). Moreover, a higher (4.72 +/-2.02), statistically significant percentage of platelets with P-selectin expression was found in patients with disseminated neoplastic changes in renal parenchyma, compared to patients with a single localized neoplastic lesion (4.17 +/-1.89) (p < 0.05). A statistically significant difference was noted in the platelet count and anisocytosis in renal cancer patients. Renal cancer enhances P-selectin expression. It is due to the presence of intensified thrombinogenesis and other platelet agonists in the blood.     

CD62p、CD63、C-RP在急性冠状动脉综合征中的作用

目的　研究血小板活化和炎症反应在急性冠状动脉综合征 (ACS)中的作用。方法　采用全血流式细胞术测定 ACS患者 5 0例和正常对照组 30例血小板胞浆内α-颗粒上的膜糖蛋白 (CD6 2 p)、溶酶体膜糖蛋白 (CD6 3) ,用速率散射比浊法测定血浆 C-反应蛋白 (C- Rective Protein,C- RP)。结果　 ACS组血小板表面活性标志蛋白 CD6 2 p(11.2 1± 0 .84 ) %、CD6 3(4 .17± 0 .4 5 ) %和 C- RP(19.16± 2 .5 8) m g/ L均明显高于对照组 (3.31± 0 .6 2 ) %、(1.5 2±0 .4 1) %和 (5 .12± 1.4 3) m g/ L(P<0 .0 1) ;CD6 2 p、CD6 3与 C- RP呈显著正相关 (相关系数分别为 0 .4 2 8和 0 .4 6 9,均 P<0 .0 1)。结论　 ACS患者存在血小板活性增强和炎症反应 ,这些变化与 ACS的病理过程有关。     

氯吡格雷联合阿司匹林对老年不稳定型心绞痛患者血小板活化的临床干预研究

目的通过观察氯吡格雷联合阿司匹林对老年不稳定型心绞痛(UAP)患者血小板活化的影响,探讨其临床意义。方法应用流式细胞仪,分别对老年UAP患者与健康老年人血小板活化标记物CD62p、CD63进行检测,同时动态观察UAP患者应用氯吡格雷联合阿司匹林治疗前后CD62p、CD63水平的变化。结果UAP患者CD62p、CD63水平高于正常对照组;氯吡格雷联合阿司匹林治疗后,UAP患者CD62p、CD63水平较单用阿司匹林明显降低,而不影响血小板体积(MPV)和血小板计数(PLT)。结论老年UAP患者血小板活化水平升高,氯吡格雷联合阿司匹林可使血小板活化受到更为明显的抑制。     

溃疡性结肠炎患者P-选择素和血小板参数分析

背景：研究发现凝血机制活化在炎症性肠病（IBD）的进展过程中起重要作用。P-选择素（CD62P）参与介导凝血和炎症反应时中性粒细胞和单核细胞与活化的血小板或内皮细胞的黏附。目的：探讨血小板活化标记物P．选择素以及血小板计数（PLT）、平均血小板体积（MPV）用于溃疡性结肠炎（UC）疾病活动度评估的价值。方法：纳入65例活动期UC患者、31例缓解期UC患者和60例健康对照者。流式细胞术测定外周血P-选择素阳性率,血细胞分析仪测定PLT、MPV,分析三者与UC活动度的相关性。结果：UC患者外周血CD62P阳性率、PLT显著高于对照组（P〈0．01）,MPV显著低于对照组（P〈0．01）;活动期UC患者三项指标的变化均较缓解期UC患者更为显著,组间差异有统计学意义（P〈0．05）。外周血CD62P、PLT与UC活动度呈正相关（P〈0．05）,MPV与UC活动度呈负相关（P〈0．05）。结论：UC患者的机体处于高凝状态。P-选择素、PLT、MPV能反映UC疾病活动度,对病情评估和治疗方案的制定有一定参考价值。     

血小板激活及内皮损伤血液标志物对心房颤动血栓栓塞危险性的评价

目的:研究心房颤动(Af)患者是否存在血小板激活和内皮损伤,探讨其对评价Af血栓栓塞危险性的价值。方法:Af患者共89例,按是否接受了经食管超声心动图(TEE)检查分为两个亚组:①TEE检查亚组:35例,发现左心房和(或)左心耳有血栓者10例,有明确外周动脉血栓栓塞并发症者8例,无血栓者17例;②未检查亚组:54例。另选33例非Af者为对照组。用ELISA法测定两组的血浆可溶性P选择素(sP选择素)、血管性血友病因子(vWF)、D二聚体(DD)水平,用全自动生化分析仪测定平均血小板体积(MPV),对其结果进行对照分析。结果:Af患者血浆sP选择素、vWF、MPV、DD水平显著升高(P<0.05),其中血浆sP选择素、DD、MPV水平在血栓和无血栓者中差异有统计学意义(P<0.05)。且sP选择素与DD水平呈正相关(r=0.311,P<0.05)。结论:Af患者存在有血小板激活及内皮损伤,与其血栓形成及栓塞并发症有一定关系。