彩色多普勒血流显像对椎动脉病变的分析研究

应用彩色多普勒血流显像技术测定３０例正常人３２例椎基底动脉缺血患者椎动脉的内径、峰值血流速度、每分钟血流量、压力降半时间、阻力指数及窗口指数。结果示正常人椎动脉内径左侧占优势（Ｐ〈０．０５）。患者患侧与健侧，正常人与患者患侧相比各指标均有显著性差异（Ｐ〈０．０１或０．００１）。结论：彩色多普勒血流显像对判定颅外脑血管的病理及机能状态，特别是椎基底动脉供血情况有重要价值。     

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.     

Increased fasting glucose and the prevalence of arterial stiffness: a cross-sectional study in Chinese adults

Abstract

Objective:

Previous studies have shown that diabetes increases the prevalence of arterial stiffness. However, it remains controversial whether impaired fasting glucose (IFG), a key pre-diabetes condition, is associated with increased risk of arterial stiffness. This study aimed to investigate the relationship between increased fasting plasma glucose (FPG) and the prevalence of arterial stiffness in a Chinese adult population.

Methods:

A random sample of 5039 participants aged 40 years or older (40·0% female) were enrolled in this study. Information on potential risk factors for cardiovascular disease was collected, and the presence of arterial stiffness was assessed by measuring brachial-ankle pulse wave velocity (baPWV). Participants were stratified into three groups: normal fasting glucose (NFG), IFG, and diabetes mellitus (DM). The IFG group was further stratified by quartiles based on the level of FPG into Q1, Q2, Q3, and Q4.

Results:

Fasting plasma glucose level was found to be independently and positively associated with baPWV. The adjusted odds ratios (ORs) (95% confidence interval (CI)) for arterial stiffness were 1·09 (0·80–1·48), 1·33 (0·98–1·81), 1·27 (0·93–1·73), 1·82 (1·31–2·53), and 2·15 (1·66–2·79) for those in IFG Q1, Q2, Q3, Q4, and DM groups compared with NFG group (P < 0·001), respectively, after adjusting for age, sex, and other potential confounders. Moreover, male participants and participants younger than 60 years were closely associated with the presence and severity of arterial stiffness (P < 0·001).

Conclusion:

Our study reports a previously unidentified positive association between increased FPG and the prevalence of arterial stiffness, suggesting the importance of FPG control in the prevention of arterial stiffness.     

D-dimer relates positively with increased blood pressure in black South Africans: The SABPA study

Introduction

Hypertension is highly prevalent in black South Africans in which morbidity and mortality from stroke are on the increase. Elevated blood pressure and haemostatic markers can induce changes in blood rheology and endothelial function which could result in a procoagulant state that increases the risk for cerebrovascular disease. Information about the coagulation and fibrinolytic systems of people from African descent are limited. We therefore, investigated the haemostatic profile and its relationships with blood pressure in black South Africans.

Materials and methods

We measured ambulatory blood pressure and haemostatic markers of 201 black and 208 white school teachers. The haemostatic markers included measurements representing coagulation and fibrinolysis (von Willebrand factor, fibrinogen, plasminogen activator inhibitor-1, fibrin D-dimer and clot lysis time).

Results

Black participants displayed significantly higher blood pressure, von Willebrand factor, fibrinogen, plasminogen activator inhibitor-1 and D-dimer levels and longer clot lysis times (p ≤ 0.001). Single, partial and multiple regression analyses showed that systolic (p ≤ 0.011) and diastolic blood pressure (p = 0.010) correlated positively with D-dimer in black participants, while systolic (p ≤ 0.001) and daytime diastolic blood pressure (p = 0.011) correlated negatively with clot lysis time in white participants.

Conclusion

The black population had a more prothrombotic profile, with higher levels of coagulation markers and inhibited fibrinolysis, than the white study participants. The positive association between blood pressure and elevated D-dimer in the blacks may contribute to the high prevalence of hypertension and related increased cardiovascular and cerebrovascular risk in this group.     

多普勒超声测定左心室Max（dp／dt）的新方法

心室内压力变化率峰值Ｍａｘ（ｄｐ／ｄｔ）是一项评价心肌收缩功能的重要指标。但其测定常需借助于心导管术，临床应用受到限制。依据流体力学基本定律，本文提出：等容收缩期内表现为压力的势能将在射血期部分地转化为以１／２ｐＶ２为形式的动能，因而势能的最大变化率Ｍａｘ（ｄｐ／ｄｔ）将在动能的最大变化率Ｍａｘ（ｄｋ／ｄｔ）上得到反映。应用特制计算机软件将主动脉血流速度曲线转化为４Ｖ２曲线，该曲线的一级导数峰值即为Ｍａｘ（ｄｋ／ｄｔ）。应用脉冲多普勒超声测定２３例先天性心脏病患儿的主动脉血流频谱参数并与心导管测定的左心室Ｍａｘ（ｄｐ／ｄｔ）进行对比分析。结果显示：主动脉血流频谱参数Ｍａｘ（ｄｋ／ｄｔ）与左心室Ｍａｘ（ｄｐ／ｄｔ）呈良好相关（ｒ＝０．８１７，Ｐ＜０．００１），直线回归方程为：Ｍａｘ（ｄｐ／ｄｔ）＝０．４７Ｍａｘ（ｄｋ／ｄｔ）＋６７．９（Ｋｐａ／ｓ），平均加速度ｍＡ及Ｖｐ２／ＡＴ与Ｍａｘ（ｄｐ／ｄｔ）亦有较好的相关性。表明由多普勒超声获得的主动脉血流频谱参数Ｍａｘ（ｄｋ／ｄｔ）能较准确地估侧左室Ｍａｘ（ｄｐ／ｄｔ），因而可作为评价心脏收缩功能的可靠指标     

Elevated alkaline phosphatase velocity strongly predicts overall survival and the risk of bone metastases in castrate-resistant prostate cancer

ObjectivesIn patients with a rising prostate-specific antigen (PSA) level during treatment with androgen deprivation therapy, identification of men who progress to bone metastasis and death remains problematic. Accurate risk stratification models are needed to better predict risk for bone metastasis and death among patients with castration-resistant prostate cancer (CRPC). This study evaluates whether alkaline phosphatase (AP) kinetics predicts bone metastasis and death in patients with CRPC.Methods and materialsA retrospective cohort study of 9,547 patients who underwent treatment for prostate cancer was conducted using the Center for Prostate Disease Research Multi-center National Database. From the entire cohort, 347 were found to have CRPC and, of those, 165 had 2 or more AP measurements during follow-up. To determine the AP velocity (APV), the slope of the linear regression line of all AP values was plotted over time. Rapid APV was defined as the uppermost quartile of APV values, which was found to be ≥6.3 IU/l/y. CRPC was defined as 2 consecutive rising PSA values after achieving a PSA nadir<4 ng/ml and documented testosterone values less than 50 ng/dl. The primary study outcomes included bone metastasis–free survival (BMFS) and overall survival (OS).ResultsRapid APV and PSA doubling time (PSADT) less than 10 months were strong predictors of both BMFS and OS in a multivariable analysis. Faster PSADT was a stronger predictor for BMFS (odds ratio [OR] = 12.1, P<0.0001 vs. OR = 2.7, P = 0.011), whereas rapid APV was a stronger predictor of poorer OS (OR = 5.11, P = 0.0001 vs. OR = 3.98, P = 0.0034). In those with both a rapid APV and a faster PSADT, the odds of developing bone metastasis and death exceeded 50%.ConclusionAPV is an independent predictor of OS and BMFS in patients with CRPC. APV, in conjunction with PSA-based clinical parameters, may be used to better identify patients with CRPC who are at the highest risk of metastasis and death. These findings need validation in prospective studies.     

Maximal Oxygen Consumption and Bone Mineral Density in a Group of Young Lebanese Adults

The aim of this study was to explore the relationship between maximal oxygen consumption (VO₂ max) and bone mineral density (BMD) in a group of young Lebanese adults. Twenty women and 37 men whose ages range from 18 to 32 yr participated in this study. Informed written consent was obtained from the participants. Body weight and height were measured, and body mass index was calculated. VO₂ max was determined by direct measurement while exercising on a bicycle ergometer (Siemens-Elema RE 820; Rodby Elektronik AB, Enhorna, Sweden). Whole body bone mineral content (WB BMC), whole body bone mineral density (WB BMD), lumbar spine BMD (L1–L4 BMD), total hip BMD (TH BMD), and femoral neck BMD (FN BMD) were measured by dual-energy X-ray absorptiometry. In women, VO₂ max (expressed as L/mn) was positively correlated to WB BMC (r = 0.82; p < 0.001), WB BMD (r = 0.80; p < 0.001), L1–L4 BMD (r = 0.73; p < 0.001), TH BMD (r = 0.80; p < 0.001), and FN BMD (r = 0.85; p < 0.001). In men, VO₂ max (expressed as L/mn) was positively correlated to WB BMC (r = 0.57; p < 0.001), WB BMD (r = 0.53; p < 0.001), L1–L4 BMD (r = 0.50; p < 0.001), TH BMD (r = 0.38; p < 0.01), and FN BMD (r = 0.30; p < 0.05). In both sexes, the positive associations between VO₂ max and bone variables (BMC and BMD) remained significant after adjustment for age (p < 0.001). This study suggests that VO₂ max (L/mn) is a positive determinant of BMC and BMD in young adults. Aerobic power seems to be a determinant of BMC and BMD in young adults.