张炜教授临证之三仁汤新用举隅

三仁汤为清代吴鞠通所著《温病条辨》中的名方,是治疗湿温病的代表方,备受后世医家喜爱,笔者依据老师张炜教授在临床上辨证应用三仁汤治疗儿科常见病(小儿厌食、荨麻疹)及疑难病(血小板减少性紫癜、肺含铁血黄素沉积症)验案举隅,探讨三仁汤在中医学的辨证论治和异病同治理论指导下,被广泛应用于临床各类疾病的治疗。     

基于“久病入络”理论探讨糖尿病视网膜病变与瘀血的关系

糖尿病视网膜病变(diabetic retinoathy,DR)属于糖尿病微血管并发症之一,近年来,其发病率有逐年升高的趋势。中医根据症状将该病称之为"视瞻昏渺""云雾移睛""暴盲""血灌瞳神",现代医学也称之为"消渴目病"。"久病入络"理论属于络病学说的核心观点之一,其由络病理论发展而来,是清代名医叶天士提出的重要观点。DR是在糖尿病的基础上发展而来,符合"久病入络"之前提,久病必虚且虚久常瘀;同时,络脉逐层分级,延伸到眼部而为目络,目之络脉众多、纤细幽深,络中血行缓慢,易于瘀滞;消渴病暗耗气血津液,目络空虚,气亏血少推动无力,终至瘀血产生。此外,从现代发病机制而言,DR主要与微循环障碍、炎症反应、氧化应激、血液流变学异常、血小板状态等有关,以上机制或可直接产生瘀血,或为瘀血的产生创造了条件。中医学将DR归属于络病范畴,络虚血瘀是其基本病机,瘀血贯穿DR的始终,是DR发生、发展变化的关键因素。"络以通为用"也是叶氏提出的观点之一,已经在诸多学科进行了应用,疗效确切。在治疗本病时,也要严格把握"络以通为用"的基本原则,针对DR之络虚和瘀血,采用补虚通络的方法,配合虫类药、风性药、散结药和入肝经的药,使亏虚之目络得补、瘀滞之目络得通,以达到了改善症状、提高视力、延缓病情进展的目的。     

植物精油对心血管疾病作用的研究进展

心血管疾病是心脏和血管方面相关的疾病,包括高血压、高脂血症、血栓栓塞、冠心病和心力衰竭等。心血管疾病严重危害人类健康,是全球范围内造成死亡的最主要原因。维护心血管系统健康的关键因素是对疾病的预防。植物精油及其部分成分能舒张血管、降血压、抗心肌缺血、预防和改善动脉粥样硬化、抗血小板聚集以及抗心律失常,从而对心血管系统具有保护作用。植物精油有益于人体的心血管系统,但需要更多的临床研究和安全性研究的证据。     

基质细胞衍生因子-1和血小板第4因子对体外扩增后脐血CD34+细胞黏附特性和趋化功能的影响

为了研究基质细胞衍生因子-1（SDF—1）和血小板第4因子（PF4）对扩增后脐血CD34^＋细胞归巢相关功能的影响，将纯化的脐血CD34^＋细胞接种入无血清培养液中，加入不同组合的细胞因子FST（FL＋SCF＋TPO）、FST＋SDF—1、FST＋PF4或FST＋SDF—1＋PF4，分别于培养第7、10、14天检测CD34^＋细胞扩增倍数、集落形成能力、细胞的黏附分子表达、总黏附性、趋化功能。结果表明：①加入SDF—1的实验组CD34^＋细胞及造血祖细胞集落扩增倍数高于对照组；②加入SDF—1明显上调扩增的CD34^＋细胞CD49e的表达，加入PF4明显上调扩增的CD34^＋细胞CD49e、CD54的表达，在扩增体系中加入SDF—1或PF4均能够明显提高扩增的CD34^＋细胞的总黏附性；③在扩增体系中加入SDF—1能够明显提高扩增的CD34^＋细胞的自发迁移率，但导致CXCR-4的表达和SDF—1诱导迁移率降低；而PF4能够明显提高扩增的CD34^＋细胞的CXCR-4的表达和SDF—1诱导迁移率；在扩增体系中同时加入SDF—1和PF4能够明显提高扩增的CD34^＋细胞自发迁移率和SDF—1诱导迁移率。结论：体外扩增体系中加入SDF—1和PF4能够上调部分归巢相关黏附分子的表达，保持扩增的CD34^＋细胞的黏附和迁移能力，有利于降低体外扩增对造血干／祖细胞（HSPC）归巢相关功能的不利影响，维持扩增的HSPC的归巢潜能。     

20(S)⁃原人参二醇止血作用及其机制

目的通过体内和体外实验研究20(S)?原人参二醇对小鼠凝血系统的作用和对人/鼠血小板的活化作用,探讨原人参二醇的止血作用及相关的作用机制。方法小鼠断尾和肝划痕法观察小鼠出血时间;自动血液分析仪检测大鼠血常规;自动凝血分析仪检测大鼠凝血四项指标;酶联免疫吸附法检测血小板中环磷酸腺苷(cAMP)和环磷酸鸟苷(cGMP)水平;Cytation 5多功能酶标仪检测洗涤人血小板内钙离子的浓度([Ca²⁺]i);比色法观察血小板的聚集率;流式细胞术检测洗涤人血小板中CD62P和PAC?1相关表达。结果原人参二醇能缩短小鼠的出血时间;增加红细胞参数中的红细胞数量(RBC)和红细胞压积(HCT),提高血小板参数中血小板数量(PLT)和血小板压积(PCT);缩短大鼠活化部分凝血活酶时间(APTT),中剂量和高剂量组可增加纤维蛋白原的表达。同时,原人参二醇能提高大鼠洗涤血小板cAMP水平、血小板内[Ca²⁺]i和血小板聚集度;增加洗涤人血小板CD62P释放和PAC?1表达。结论原人参二醇具有一定的止血作用,一方面通过激活大鼠的内源性凝血系统,影响体内血小板和红细胞参数,促进血浆中纤维蛋白原生成;另一方面通过影响钙离子和cAMP信号通路,增加血小板Ca²⁺内流、CD62P释放和促进PAC?1的表达,最终诱导血小板聚集,形成血栓,发挥止血作用。     

The influence of body size on the pharmacodynamic and pharmacokinetic response to clopidogrel and prasugrel: A retrospective analysis of the FEATHER study

Introduction

Patients treated with clopidogrel who have higher body size exhibit greater platelet reactivity than patients with lower body size. In a retrospective analysis of the FEATHER trial, we examined the relationship between platelet response to thienopyridines clopidogrel 75 mg (Clop-75), prasugrel 5 mg (Pras-5), and prasugrel 10 mg (Pras-10) using 3 body size indices: body weight (BW), body mass index (BMI), and body surface area (BSA). Relationships were assessed as continuous variables and as 4 incremental body size groups.

Materials and Methods

Aspirin-treated patients with stable coronary artery disease (N = 72) and a BW range of 45-134 kg received Clop-75, Pras-5, and Pras-10 in a 3-period, blinded, cross-over study. Platelet assays included maximum platelet aggregation (MPA) to 20 μM ADP by light transmission aggregometry, VerifyNow-P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein (VASP) phosphorylation platelet reactivity index (PRI). Exposure to active metabolites (AMs) was also assessed.

Results

Body size was a determinant of AM exposure and residual platelet reactivity regardless of type and dose of thienopyridine. BW and BSA demonstrated marginally stronger correlations with platelet reactivity; VASP-PRI demonstrated a stronger correlation with the body size than the other tests. Correlation coefficients ranged from a high of 0.64 (BW vs. PRI on Pras-5) to a low of 0.34 (BMI vs. MPA on Pras-10), but all were statistically significant (p < 0.01).

Conclusions

Using a comprehensive selection of body size indices, AM exposures, platelet function tests, and thienopyridine doses, we demonstrated a consistent inverse relationship between body size and response to clopidogrel and prasugrel.     

Increased thrombin generation in splanchnic vein thrombosis is related to the presence of liver cirrhosis and not to the thrombotic event

Introduction

In recent years there have been increasing evidence associating liver disease with hypercoagulability, rather than bleeding. The aim of the study was to evaluate the haemostatic potential in patients with liver disease.

Patients and methods

We measured thrombin generation in the presence and absence of thrombomodulin in patients with portal vein thrombosis (PVT, n = 47), Budd-Chiari syndrome (BCS, n = 15) and cirrhosis (n = 24) and compared the results to those obtained from healthy controls (n = 21). Fifteen patients with PVT and 10 patients with BCS were treated with warfarin and were compared to an equal number of patients with atrial fibrillation matched for prothrombin time-international normalized ratio. We assessed resistance to thrombomodulin by using ratios [marker measured in the presence/absence of thrombomodulin].

Results

There were no differences in thrombin generation between patients on warfarin treatment and their controls. Cirrhotic patients generated more thrombin in the presence of thrombomodulin and exhibited thrombomodulin resistance compared to controls [p = 0.006 for endogenous thrombin potential (ETP) and p < 0.001 for peak thrombin and both ratios ETP and peak] and patients with non-cirrhotic PVT (p = 0.001, p = 0.006, p < 0.001, p < 0.001 for ETP, peak, ratio ETP, ratio peak, respectively). The patients with cirrhotic PVT exhibited higher ETP (p = 0.044) and peak (p = 0.02) in the presence of thrombomodulin than controls, as well as thrombomodulin resistance (ETP and peak ratios: p = 0.001).

Conclusions

Hypercoagulability and thrombomodulin resistance in patients with cirrhosis were independent of the presence of splanchnic vein thrombosis. The hypercoagulability in patients with cirrhotic PVT could have implications for considering longer or more intensive treatment with anticoagulants in this group.     

Measurement of thrombin generation intra-operatively and its association with bleeding tendency after cardiac surgery

Introduction

Patients undergoing cardiac surgery with cardiopulmonary bypass (CPB) are susceptible to haemostatic disturbances. Monitoring the haemostatic capacity by conventional clotting tests is challenging.

Materials and Methods

Thrombin generation (TG) by Calibrated Automated Thrombography, clotting tests and tissue factor pathway inhibitor (TFPI) measurements were performed to describe the relationship between haemostatic changes and alterations in these tests. Blood samples were collected before, during and after CPB. Furthermore, it was investigated whether TG measured intraoperatively, is associated with increased risk of bleeding postoperatively.

Results

TG diminished significantly (p < 0.01) after heparinization in the presence and absence of platelets (37% and 50%) compared to baseline. After the start of CPB, TG elevated and persisted till the end of surgery but remained lower than preoperatively. Activated clotting time increased after heparinization and after the start of bypass compared to baseline (400% and 500%). Anti-FXa activity reduced on the start of CPB compared to the level after heparinization, to almost the baseline value following protamine reversal of heparin. The plasma levels of total and free TFPI elevated 9 and 14 fold during bypass and remained after protamine administration higher than preoperatively. Plasma D-dimer levels reduced (p < 0.01) when bypass started. However, a marked elevation was observed in the following time points. TG in platelet-rich plasma measured after heparinization and after the start of CPB associated (p < 0.05) with postoperative blood loss.

Conclusions

TG can be determined during CPB despite the high heparinization level, it reflects the haemostatic capacity better than clotting-based assays and might better predict bleeding when performed intraoperatively.     

Evaluation of a chromogenic commercial assay using VWF-73 peptide for ADAMTS13 activity measurement

Introduction

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy (TMA), related to a severe functional deficiency of ADAMTS13 activity (< 10% of normal). ADAMTS13 activity is thus crucial to confirm the clinical suspicion of TTP, to distinguish it from other TMAs, and to perform the follow-up of TTP patients.

Material and methods

We compared the performance of the commercial chromogenic assay Technozym® ADAMTS13 Activity ELISA (chromogenic VWF73 substrate, Chr-VWF73, Technoclone, Vienna, Austria), to that of our in-house FRETS-VWF73 used as reference method. A large group of 247 subjects (30 healthy volunteers and 217 patients with miscellaneaous TMAs) was studied.

Results

The lower limit of detection of the Chr-VWF73 was 3%, which is well adapted to the clinically relevant threshold for TTP diagnosis (10%). Our results showed a reasonable agreement between FRETS-VWF73 and Chr-VWF73 assays to distinguish samples with an ADAMTS13 activity < 10% from those with an ADAMTS13 activity > 10%. However, Chr-VWF73 assay provided false negative results in ~ 12% of acute TTP patients. Inversely, the Chr-VWF73 assay globally underestimated ADAMTS13 activity in detectable values ranging from 11 to 100% (with a great variability compared to FRETS-VWF73), which may be a concern for the follow-up of TTP patients in remission.

Conclusion

In-house assays developed and performed by expert laboratories remain the reference methods that should be used without limitation to control values provided by commercial assays when needed. Also, the development of an international reference preparation will be crucial to improve standardization.