Clinical significance of platelet mononuclear cell aggregates in patients with sepsis and acute respiratory distress syndrome

BACKGROUND The diagnosis of sepsis combined with acute respiratory distress syndrome(ARDS)has increased owing to the enhanced awareness among medical profes-sionals and the continuous development of modern medical technologies,while early diagnosis of ARDS still lacks specific biomarkers.One of the main patho-genic mechanisms of sepsis-associated ARDS involves the actions of various pathological injuries and inflammatory factors,such as platelet and white blood cells activation,leading to an increase of surface adhesion molecules.These adhesion molecules further form platelet-white blood cell aggregates,including platelet-mononuclear cell aggregates(PMAs).PMAs has been identified as one of the markers of platelet activation,here we hypothesize that PMAs might play a potential biomarker for the early diagnosis of this complication.METHODS We selected 72 hospitalized patients diagnosed with sepsis as the study population between March 2019 and March 2022.Among them,30 patients with sepsis and ARDS formed the study group,while 42 sepsis patients without ARDS comprised the control group.After diagnosis,venous blood samples were imme-diately collected from all patients.Flow cytometry was employed to analyze the expression of PMAs,platelet neutrophil aggregates(PNAs),and platelet aggregates(PLyAs)in the serum.Additionally,the Acute Physiology and Chronic Health Evaluation(APACHE)II score was calculated for each patient,and receiver operating characteristic curves were generated to assess diagnostic value.RESULTS The study found that the levels of PNAs and PLyAs in the serum of the study group were higher than those in the control group,but the difference was not statistically significant(P>0.05).However,the expression of PMAs in the serum of the study group was significantly upregulated(P<0.05)and positively correlated with the APACHE II score(r=0.671,P<0.05).When using PMAs as a diagnostic indicator,the area under the curve value was 0.957,indicating a high diagnostic value(P<0.05).Furthermore,the optimal cutoff value was 8.418%,with a diagnostic sensitivity of 0.819 and specificity of 0.947.CONCLUSION In summary,the serum levels of PMAs significantly increase in patients with sepsis and ARDS.Therefore,serum PMAs have the potential to become a new biomarker for clinically diagnosing sepsis complicated by ARDS.

Preservation of platelet function in patients with cirrhosis and thrombocytopenia undergoing esophageal variceal ligation

Background:Thrombocytopenia is a possible risk factor for bleeding after band ligation of esophageal varices.However,elevated von Willebrand factor(VWF)in cirrhosis improves platelet function and could decrease this risk.Our objective was to assess platelet function in patients with cirrhosis undergoing esophageal variceal ligation(EVL).Methods:The assessment consisted of platelet count,antigen and activity of VWF and VWF-cleaving protease ADAMTS-13 activity,and a platelet adhesion and aggregation test simulating vascular flow in vivo(Impact-RR)prior to EVL.Results:Totally 111 patients were divided into three groups according to platelet count:(1)<50×109/L(n=38,34.2%);(2)50×109/L to 100×109/L(n=47,42.3%);and(3)>100×109/L(n=26,23.4%).No statistically significant difference was found in the aggregate size of platelets[group 1:41.0(31.8–67.3)μm 2;group 2:47.0(33.8–71.3)μm 2;and group 3:47.0(34.0–66.0)μm 2;P=0.60]and no significant correlation was found between aggregate size and platelet count(Spearman r=0.07;P=0.47).Surface coverage was 4.1%(2.8%–6.7%),8.5%(4.0%–10.0%),and 9.0%(7.1%–12.0%)(P<0.001)in groups 1,2 and 3,respectively and correlated with platelet count(Spearman r=0.39;P<0.0001).There was no significant difference between groups in VWF or ADAMTS-13.Post-EVL bleeding occurred in six(5.4%)patients(n=2 in group 1,n=1 in group 2,and n=3 in group 3;P=0.32).Patients with bleeding had higher MELD scores[15.0(11.3–20.3)versus 12.0(10.0–15.0);P=0.025],but no difference was demonstrated for platelet function parameters.Conclusion:Platelet function is preserved even in the presence of thrombocytopenia,including in the patients with post-EVL bleeding.

Effects of Total Flavone of Abelmoschl Manihot L.Medic on the Function of Platelets and Its Mechanism

Objective: To study the effects of total flavone of Abelmoschl Manihot L.Medic (TFA) on the function of platelets and to explore its mechanism. Methods: Rat models of artery-veins bypassing thrombus formation were used. The platelets of rabbits were collected. Platelet aggregation was induced by collagen and intracellular calcium ion concentration ([Ca 2+ ]i) was assayed by Fura-2 method. Results: TFA (25, 50, 100 mg/kg) significantly and dose-dependently reduced the weight of thrombus. TFA (0.025, 0.05, 0.1 mg/ml) possessed dose-dependant inhibitory effects on rabbits' platelet aggregation induced by collagen. TFA significantly reduced the resting and CaCl 2-induced increase of free intracellular calcium concentration ([Ca 2+ ]i) in rabbit platelet in vitro . Conclusion: TFA has an antiplatelet effect via the inhibition on the influx of Ca 2+ .

Synthesis of Novel Ligustrazine Derivatives as Potential Platelet Aggregation Inhibitors

A series of novel ligustrazine derivatives were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, ^1H NMR and ESI-MS. The preliminary antiplatelet aggregation screening results demonstrated that the compounds 7a, 7b and 7c showed higher potency than ligustrazine.

Effect of SJAMP on ATP Release of Platelet

The aggregation and ATP release of placelet of normal subjects were measured by platelet lumi aggregometer. It was found that the aggregation curve induced by SJAMP at the concentration of 100 mg/L was a typical second phase aggregation. There existed a certain lag between platelet aggregation and secretion. The secretion actually began slightly after the second phase of aggregation, suggesting that the second phase aggregation induced by SJAMP is not dependent upon the release of contents of dense granule alone. If platelets were incubated with cyclo oxygenase inhibitor, the second phase aggregation was inhibited and no ATP was released. The results indicated that the aggregation and release reaction induced by SJAMP were dependent upon the generation of prostaglandin endoperoxides and TXA 2 in normal subjects. The amount of ATP release was 0.69±0.22 nmol/10 8 platelets as stimulated with SJAMP (100 mg/L). But the amount of ATP release were 1.60±0.25 and 1.37±0.15 nmol/10 8 platelets when platelets were stimulated with ADP (5 μmol/L) and collagen (5 mg/L). The amount of ATP release induced by SJAMP was significantly lower than that of ADP and collagen. These findings indicated that SJAMP was a weaker agonist than ADP in terms of platelets release reaction.

Platelet aggregation responses in type 2 diabetic patients

Diabetes mellitus (DM) is associated with platelet dysfunction. In diabetic patients, alterations in platelet functions, especially increased platelet agregation, have been suggested to cause increasing in cardiovascular morbidity and mortality or in accelaretion of athersclerotic process. In this study, we aimed to investigate the platelet aggregation response alterations and the effects of DM duration, HbA1c, treatment options among the patients with Type 2 DM. Fortyfive patients (case group;21 male, 24 female) with Type 2 DM and forty-eight healthy individuals (control group;22 male, 26 female) were included in this study. Platelet aggregation was determinated with Chorono-log 500 (USA) named device by using Chorono-log/ADP, Chorono-log/ collagen and Chorono-log/epinephrine kits. ADP-induced platelet aggregation was significantly higher in the case group compared with control group (p 【0.05). Epinephrine induced platelet aggregation were significant in negatively correlation with the diabetes duration (P 【0.05). Platelet aggregation responses did not differ according to their treatment type (sulphonylurea or insulin) was statistically insignificiant among the case groups (p 】0.05). In conclusion, our findings supported that type 2 diabetes may interfere with platelet functions without any relationship age, gender, the treatment types and the regulation levels. These findings supports that existence potential new factors or mechanism affecting platelet agregation. The subject requires more detailed studies in the future.

前列腺素E1对原发性肾病综合征作用初探(英文)

Objective:To investigate the effect of prostaglandin E1 (PGE1) (Alprostadii injection) on patients with primary nephrotic syndrome(PNS). Methods: 37 patients with PNS were recruited to study the effect of prostaglandin E1 on platelet aggregation function [ PAG (5,) PAG( m ) ], serum total protein (TP) , albumin (Al),blood urea nitrogen(BUN) ,serum creatinine(Scr) ,cholesterol(CHO), triglyceride(TG), protein in 24-hour urine (Pr/24h) and platelet account (PLT). Results: TP, Al, CHO, TG, BUN, Scr, Pr/24h, PAG(5) and PAG(m) in PNS group before treatment were significantly different from those in control group(P＜0.05, P＜0.01) while no significant difference was found for PLT. When treated with PGE1 , TP,Al,CHO, TG, Pr/24h, ADP- induced PAG(5) ,and Adr- induced PAG(5) and PAG(m) were significantly different from those before treatment (P＜0.05). Adr- induced PAG(5) and PAG(m) were significantly different. Adr- induced PAG(5) was xsitively correlated with BUN and Scr in PNS(P＜0.01). Similar correlation was found between ADP-induced PAG(5) and Al ,BUN,Scr,Pr/24h(P＜0.05), AD- induced PAG(m) and TP,CHO(P＜0.05). Conclusions: PGE1 may be an effective drug for the treatment for hypercoagulation in patients with PNS.

Safety, Pharmacokinetic and Pharmacodynamic Studies of Batifiban Injection Following Single-and Multiple-Dose Administration to Healthy Chinese Subjects

Batifiban, a synthetic cyclic peptide, is a potent platelet glycoprotein GPⅡb/Ⅲa antagonist which may be useful in the treatment and prevention of acute coronary syndromes. The pharmacokinetics and pharmacodymanic （inhibition of platelet aggregation） effects, and tolerability of batifiban were investigated in healthy subjects following single bolus injection with doses of 55, 110, or 220 μg/kg, or multiple doses of an bolus followed intravenous infusion for 24 h （180 μg/kg plus 2.0 μg/minokg, and 220 μg/kg plus 2.5μg/minokg） in this phase I clinical trial. Plasma levels of batifiban and areas under the curve were found to be proportional to doses. Batifiban was rapidly eliminated with a half-life of approximately 2.5 h. Significant differences were noted for plasma levels of batifiban and areas under the curve between males and females. No significant differences in the terminal half-life were found between males and females. Batifiban reversibly inhibited ex vivo platelet aggregation in a dose- and concentration-dependent manner, consistent with its mechanism as a GPⅡ b/Ⅲa antagonist. Single and multiple intravenous doses of batifiban were found to be safe and well tolerated in healthy subjects. These results support a bolus injection plus intravenous infusion regimen of batifiban for the treatment and prevention of acute coronary syndromes.

Hypoglycemic Activity of Jatrorrhizine

Summary： The hypoglycemic activity and its mechanism of Jatrorrhizine （Jat） were studied. The normal mice and alloxan-induced hyperglycemic mice were given with different doses of Jat. Blood glucose and liver glycogen levels were determined by spectrophotometry with glucose-oxidase and iodine reagents respectively. The levels of blood lactic acid （LC） and liver lactate dehydrogenase （LDH） activity were measured to explore the effect of Jat on anaerobic glycolysis. Succinate dehydrogenase （SDH） activity in liver was measured to evaluate the effect of Jat on aerobic glycolysis in liver. It was found that Jat （50 mg/kg, 100 mg/kg） could significantly decrease blood glucose level in a dose- and time-dependent manner in both normal and alloxan-diabetic mice, increase the activity of SDH, but had no significant effects on the LC level and LDH activity. Jat could significantly reduce the content of liver glycogen in normal mice. Moreover, Jat could inhibit the platelet aggregation in rabbits in vitro in a dose-effect relationship. It was concluded that Jat induced the pronounced decrease in blood glucose in normal and hyperglycemic mice. The hypoglycemic activity of Jat may be attributed to the enhancement of aerobic glycolysis.

Effect of Yiqitongyanghuatan Recipe on Experimental Atherosclerosis in Rabbits

In order to investigate the roles of Yiqitongyanghuatan (YQTYHT) recipe in reducing the levels of serum cholesterol and plasma lipid peroxidation(LPO), platelet aggregation function (PAgF) and platelet adhesion function (PAdF), the area of atherosclerotic plague coverage in aorta and the thickness of plague, 32 male Japanese white rabbits were divided into 4 groups. The results showed that the YQTYHT recipe could significantly lower the levels of serum cholesterol and tryglyceride, plasma LPO, and PAgF and PadF. The area of atherosclerotic plague coverage in aorta and the thickness of plague in the YQTYHT fed rabbits were decreased as compared with that in the high cholesterol fed rabbits. The above roles might contribute to the main mechanism of YQTYHT against atherosclerosis.

Antithrombotic treatment in chronic heart failure and sinus rhythm: Systematic review

AIM: To assess the efficacy and safety of antithrombotic drugs(antiplatelet or anticoagulant drugs) compared to no antithrombotic treatment or placebo in patients with heart failure(HF) and sinus rhythm. METHODS: We searched Medline and Cochrane Library for randomized controlled trials evaluating antithrombotic treatment and no antithrombotic treatment in patients with HF and sinus rhythm. Risk ratio(RR) and 95%CIs were estimated performing meta-analysis with random effects method. RESULTS: Two studies met the inclusion criteria: Heart failure Long-term Antithrombotic Study and Warfarin/Aspirin Study in Heart failure, with 336 patients and mean follow-up 1.8-2.25 years. Stroke risk was not reduced by acetylsalicylic acid(RR = 1.18, 95%CI: 0.17-8.15), oral anticoagulation(RR = 0.30, 95%CI: 0.03-2.65) or overall antithrombotic drugs(RR = 0.52, 95%CI: 0.10-2.74). Acetylsalicylic acid showed a significant increased risk of worsening HF(RR = 1.78, 95%CI: 1.08-2.92), while oral anticoagulation had no impact in this outcome(RR = 1.03, 95%CI: 0.61-1.75). Overall antithrombotic drugs showed a significant risk increase of major bleeding(RR = 6.99, 95%CI: 0.89-54.64). CONCLUSION: Best available evidence does not support the routine use of antithrombotic drugs in patients with HF and sinus rhythm. These drugs, particularly oral anti-coagulation has the hazard of increase significantly major bleeding risk.

Chemical Constituents from the Whole Plant of Cuscuta reflexa

Two new 2H-pyran-2-one glucosides,cuscutarosides A(1)and B(2),and one new steroidal glucoside,7β-methoxy-β-sitosterol 3-O-β-glucopyranoside(3),together with 12 known compounds(4-15)were isolated from the whole plant of Cuscuta reflexa(Convolvulaceae)collected from Myanmar.The chemical structures of these new compounds were elucidated based on extensive spectroscopic analysis.The antiobesity activity of these isolates was evaluated using porcine pancreatic lipase(PPL),and the antiplatelet aggregation activity was screened using rabbit platelets induced by thrombin,platelet-activating factor(PAF),arachidonate(AA),or collagen.7β-Methoxy-β-sitosterol 3-O-β-glucopyranoside(3)showed weak PPL inhibitory activity.Cuscutaroside A(1),its acetylated derivative(1a),and scrophenoside B(8)showed weak inhibitory activity against rabbit platelet aggregation induced by collagen.Compound 1a also showed inhibitory activity against rabbit platelet aggregation induced by AA.

THE EFFECT OF PAEONIA RUBRA 801 ON THE OCCURRENCE OF LUNG METASTASES IN WALKER 256 TUMOR

The development of lung nodules from intravenously injected Walker 256 (W256) tumor cells was the model system for metastases formation in this experiment. The influence and inhibitory mechanisms of a synthetic Paecnia rubra 801 (P801) on occurrence of lung metastases were investigated. The results showed that treatment with P801 alone or in combination with decoction of Huangqi (Astragalus root) can significantly reduce the number of lung nodules. The mechanisms responsible for decreased colonyforming potential in the rats treated with P801 were investigated. ADP-induced or W256 tumor cell-induced platelet aggregation was markedly inhibited by P801. It appears that inhibitory effect of P801 on occurrence of W256 tumor lung nodules is mainly due to reduced blood coagulability and inhibition of platelet activation by tumor cells.

Hawanoids A–E, unprecedented diterpenoids with PAF-induced platelet aggregation inhibitory activities from the deep-sea-derived fungus Paraconiothyrium hawaiiense

Hawanoids A–E(1–5), five highly cyclized diterpenoids were isolated from the deep-sea-derived fungus Paraconiothyrium hawaiiense FS482. Compounds 1 and 2 possessed an unprecedented tetracyclo[6.6.2.0^(2,7).0^(11,15)]cetane carbon skeleton while 3 and 4 possessed an unusual 11,14-macrocyclic ether moiety in phomactin family. Their structures including the stereo-chemistry were determined through spectroscopic analysis, X-ray diffractions and computational calculations. The plausible biosynthetic pathway was proposed based on the predicted biosynthetic gene cluster. All of the isolated compounds exhibited inhibitory activities against PAF-induced platelet aggregation. The molecular docking study was carried out understand the interaction between the PAF receptor and hawanoids with different skeletons.

A prospective randomized antiplatelet trial of cilostazol versus clopidogrel in patients with bare metal stent

Background Cilostazol is a newly developed antiplatelet drug that has been widely applied for clinical use. Its antiplatelet action appears to be mainly related to inhibition of intracellular phosphodiesterase activity. Recently, cilostazol has been used for antiplatelet therapy after coronary bare metal stent implantation for thrombosis and restenosis prevention. This prospective randomized and double blind trial was designed to investigate the safety and efficacy of cilostazol for the prevention of late restenosis and acute or subacute stent thrombosis. Methods One hundred and twenty patients who underwent elective stent were randomly assigned to treatment group with cilostazol 200 mg/d （n = 60）, clopidogrel 75 mg/d and aspirin 100 mg/d or to control group with clopidogrel treatment 75 mg/d （n = 60） and aspirin 100 mg/d. Follow-up coronary angiography was performed 6--9 months later. Results Nine months major adverse cardio-cerebral event （MACCE） were lower in treatment groups （P〈0.05）. The quantitative coronary angiography （QCA） at 6 months follow-up showed that minimum lumen diameter （MLD） was higher in treatment group than that of control group [（2.14 ± 0.52）mm vs （1.82 ± 0.36）mm, P〈0.05]. Late lumen loss （LL） [（0.82 ± 0.42）mm vs （1.31 ± 0.58）mm; P〈0.01 ], restenosis rate （RR） （14% vs 32%; P〈0.05） and target lesion revascularizaion （TLR） rate （5% vs 17%; P〈0.05） were lower in treatment group than in control group. Conclusion Cilostazol therapy is an effective regimen for prevention not only stent thrombosis but also RR and TLR through reducing MLD without the risk of increasing bleeding.

Use of tailored loading-dose clopidogrel in patients undergoing selected percutaneous coronary intervention based on adenosine diphosphate-mediated platelet aggregation

Background Adenosine phosphate-mediated platelet aggregation is a prognostic factor for major adverse cardiac events in patients who have undergone selective percutaneous coronary interventions. This study aimed to assess whether an adjusted loading dose of clopidogrel could more effectively inhibit platelet aggregation in patients undergoing selected percutaneous coronary intervention.Methods A total of 205 patients undergoing selected percutaneous coronary intervention were enrolled in this multicenter, prospective, randomized study. Patients receiving domestic clopidogrel （n=104） served as the Talcom （Taijia）group; others （n=101） received Plavix, the Plavix group, Patients received up to 3 additional 300-mg loading doses of clopidogrel to decrease the adenosine phosphate-mediated platelet aggregation index by more than 50% （the primary endpoint） compared with the baseline. The secondary endpoint was major adverse cardiovascular events at 12 months.Results Compared with the rational loading dosage, the tailored loading dosage better inhibited platelet aggregation based on a ＞50% decrease in adenosine phosphate-mediated platelet aggregation （rational loading dosage vs. tailored loading dosage, 48% vs. 73%, P=0.028）. There was no significant difference in the eligible index between the Talcom and Plavix groups （47% vs. 49% at 300 mg; 62% vs. 59% at 600 mg; 74% vs. 72% at 900 mg; P ＞0.05） based on a standard adenosine diphosphate-mediated platelet aggregation decrease of ＞50%. After 12 months of follow-up, there were no significant differences in major adverse cardiac events （2.5% vs. 2.9%, P=5.43）. No acute or subacute stent thrombosis events occurred.Conclusion An adjusted loading dose of clopidogrel could have significant effects on antiplatelet aggregation compared with a rational dose, decreasing 1-year major adverse cardiac events in patients undergoing percutaneous coronary interventions based on adenosine phosphate-mediated platelet aggregation with no increase in bleeding.

Effect of Aqueous Extracts of Several Kinds of Herbs on Human Platelet Aggregation and Expression of P-Selectin in Vitro

Objective： To study the effect of aqueous extract of several kinds of herbs on human platelet aggregation and expression of P-selectin in vitro. Methods： Blood was collected from volunteers. Effects of the prepared water extracts of herbs on platelet aggregation were monitored on a Packs-4 aggregometer. The fluorescence intensity of water extracts of Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae on the expression of P-selectin in human platelets of healthy persons was measured with flow cytometry. Results： Out of several herbs investigated, Flos Carthami and Rhizoma Curcumae potently inhibited platelet aggregation after incubation with platelet-rich plasma （PRP） for 15 min. Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae inhibited adenosine-5＇-diphosphate （ADP） or platelet activating factor （PAF）-induced platelet aggregation in PRP in a dose-dependent manner. In contrast to Flos Carthami and Rhizoma Curcumae, Caulis Spatholobi could not inhibit thrombin-induced platelet aggregation. Despite its inability to inhibit thrombin-induced platelet aggregation in PRP, Caulis Spatholobi had a greater anti-aggregating activity in PRP induced by ADP or PAF. Caulis Spatholobi and Flos Carthami showed significant inhibitory effects on the expression of P-selectin. Conclusions： Caulis Spatholobi, Flos Carthami and Rhizoma Curcumae have potent anti-platelet properties, and their inhibitory actions are mediated via different mechanisms. Caulis Spatholobi inhibited ADP-induced platelet aggregation but not by thrombin, indicating that its mechanism of action might be independent of the thromboxane pathway. The effect of Caulis Spatholobi and Flos Carthami were associated with suppressing the expression of P-selectin.

Effect on platelet aggregation activity: extracts from 31 Traditional Chinese Medicines with the property of activating blood and resolving stasis

OBJECTIVE: To evaluate the anti-platelet aggregation effects of extracts from 31 Traditional Chinese Medicines(TCM) with the property of activating blood and resolving stasis in terms of TCM theory.METHODS: The 31 TCMs extracts were prepared using water, 90% ethanol and ethyl acetate., and the effects on anti-platelet aggregation were tested on a platelet aggregation analyzer in vitro with adenosine 5'-diphosphate, bovine thrombin and arachi-donic acid(AA) as aggregation inducers, respectively. Aspirin was the positive control.RESULTS: Lots of the tested TCMs had inhibitory effects with concentration-dependent manner on platelet aggregations induced by various agonists.Especially, some of the TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae) showed good anti-platelet aggregation effect similar or higher than that in positive control group.CONCLUSION: The study provided scientific references that several TCMs such as Chuanxiong(Rhizoma Chuanxiong), Yanhusuo(Rhizoma Corydalis Yanhusuo) and Danshen(Radix Salviae Miltiorrhizae),possess the property of anti-platelet aggregation.