Fractional flow reserve and complex coronary pathologic conditions.

Fractional flow reserve (FFR) is a well-validated index for assessing the physiologic significance of a coronary stenosis in most clinical conditions encountered in today's catheterisation laboratory. The aim of this paper is to provide a short overview of the theoretical background of the coronary pressure-derived FFR index and its clinical applicability in guiding complex coronary intervention procedures.     

Effects of iomeprol,a new nonionic contrast medium,vis a vis iopamidol and nitroglycerin,on coronary diameter and blood flow in chronically instrumented dogs

The effects of an intracoronary administration of iomeprol, a new nonionic tri-iodinated water-soluble contrast medium, on coronary circulation were compared to those of iopamidol and those of nitroglycerin in 6 chronically instrumented conscious dogs. A pair of 10 MHz piezoelectric crystals and an electromagnetic flow probe were placed on the left circumflex coronary artery (LCCA) to measure the epicardial coronary diameter (CD) and coronary blood flow (CBF). Polyethylene tubing for drug administration was inserted into the LCCA proximal to the sonomicrometers. Iomeprol at the dose of 1 ml and 3 ml/min for 1 min significantly increased CD by 0.6±0.1% and 1.4±0.3%, respectively and CBF by 44.5±9% and 70±10%, respectively. Iopamidol at the same rates also significantly increased CD by 0.8±0.1% and 1.5±0.3% and CBF by 50±11% and 82±14%, respectively. There was no statistically significant difference between iomeprol-and iopamidol-induced increases in CD and CBF. However, the duration of the increase in CD was significantly shorter (p<0.05) after iomeprol than after iopamidol. Nitroglycerin (10 μg/kg) significantly increased CD by 4.5±1% and CBF by 105±10%. The increases in CD and CBF in response to iopamidol and iomeprol were significantly smaller (p<0.01) than to nitroglycerin. We conclude that vasodilating effects of iomeprol and iopamidol on the large epicardial coronary artery and coronary blood flow are comparable in conscious dogs and significantly lower than after nitroglycerin in the doses used by us. This study was supported by a grant from the EI-ZA1 Pharmaceutical Co., Tokyo, Japan.     

稳定层流剪应力对内皮细胞骨架调节蛋白VASP表达的影响

为探讨生理强度的稳定层流剪应力对内皮细胞骨架actin相关蛋白VASP特征影响规律，我们采用胰蛋白酶消化法分离人脐静脉内皮细胞(HUVECs)，模拟体内流动环境，建立平行板流动腔模型。利用细胞图像分析系统和ALEXA488—若丹明一次毒蕈环肽双标记法，观察内皮细胞在稳态层流下形态、actin排列变化与VASP分布变化之间的规律。采用Western blot定量动态检测细胞内VASP表达及磷酸化的水平。结果表明，内皮细胞在10dyn／cm^2剪切作用后，随时间细胞逐渐延长，长轴趋于剪应力作用方向排列，细胞与静息态的细胞相比，细胞内骨架沿剪应力方向重组，与此同时VASP表达增强，沿着actin纤维呈点状分布，尤其集中在细胞膜下actin末端区域；Western blot检测显示在剪切后，细胞内VASP出现快速磷酸化，VASP总体表达量增加，2h达高峰后逐渐恢复，8h后再次逐渐升高。以上结果提示血流动力学特性中剪应力引起了细胞胞质内骨架蛋白分子重组，血管内皮细胞形态改变，在此过程中，VASP发挥骨架调节蛋白的作用。     

La vasodilatation a-t-elle un rôle dans la migraine ? Non

IntroductionThe hypothesis that migraine pain is caused by vasodilation has been challenged by clinical and experimental evidence.State of artThe most convincing arguments against the vascular hypothesis come from neuroimaging data. Magnetic resonance imaging studies show that spontaneous migraine attacks are not accompanied by extracranial vasodilation, and by only slight dilation of the intracranial arteries. Pharmacologically-induced migraine attacks also provide further evidence against the role of vasodilation in migraine. Vasodilators such as sildenafil and nitroglycerine trigger attacks without dilation of the middle cerebral artery diameter, whereas VIP (vasoactive intestinal peptide) markedly dilates intra- and extracranial arteries but does not induce migraine attacks. Clinical studies also show a lack of correspondence between the subjective experience of throbbing headache and the arterial pulse. Moreover, many acute anti-migraine agents are not vasoconstrictors.PerspectivesFurther studies are necessary to clarify the mechanisms of migraine headache generation.ConclusionsContrary to a longstanding and widespread belief, vasodilatation is neither sufficient nor necessary to cause migraine headache and is probably an epiphenomenon.     

槲皮素与芦丁对离体大鼠主动脉环的舒张作用及机制

目的:比较研究槲皮素与芦丁对离体大鼠胸主动脉环的作用及其可能的途径。方法:采用累积加药法,检测槲皮素和芦丁对去氧肾上腺素(pheny lephrine,PE)预收缩的胸主动脉环张力的影响。结果:槲皮素对离体大鼠内皮完整和去内皮的胸主动脉环均有浓度依赖性的舒张作用,而芦丁对PE预收缩血管的舒张作用是内皮依赖性的。槲皮素和芦丁对内皮完整的胸主动脉环的最大舒张反应分别为(77.20±6.11)%和(44.28±7.48)%,但两者对内皮完整的胸主动脉环最大舒张的半数有效浓度无明显差异。用一氧化氮合酶抑制剂L-NAM E(0.1 mm o l/L)预处理后,可阻断芦丁诱导的舒张血管作用,但不能阻断槲皮素引起的舒张血管作用;用鸟苷酸环化酶抑制剂亚甲蓝(10μm o l/L)预处理后,两者的血管舒张作用均被阻断。用环氧合酶抑制剂吲哚美辛(10μm o l/L)预处理后可减弱槲皮素诱导的舒张血管作用,但不能阻断芦丁引起的舒张血管作用。结论:槲皮素的舒血管作用强于芦丁,槲皮素可能是通过鸟苷酸环化酶和环氧合酶途径产生非内皮依赖性的血管舒张作用,而芦丁可能是通过NO-鸟苷酸环化酶途径产生内皮依赖性的血管舒张作用。     

Non-occlusive mesenteric ischemia: etiology, diagnosis, and interventional therapy

Non-occlusive mesenteric ischemia (NOMI) compromises all forms of mesenteric ischemia with patent mesenteric arteries. It generally affects patients over 50 years of age suffering from myocardial infarction, congestive heart failure, aortic insufficiency, renal or hepatic disease and patients following cardiac surgery. Non-occlusive disease accounts for 20-30% of all cases of acute mesenteric ischemia with a mortality rate of the order of 50%. Acute abdominal pain may be the only early presenting symptom of mesenteric ischemia. Non-invasive imaging modalities, such as CT, MRI, and ultrasound, are able to evaluate the aorta and the origins of splanchnic arteries. Despite the technical evolution of those methods, selective angiography of mesenteric arteries is still the gold standard in diagnosing peripheral splanchnic vessel disease. In early non-occlusive mesenteric ischemia, as opposed to occlusive disease, there is no surgical therapy. It is known that mesenteric vasospasm persists even after correction of the precipitating event. Vasospasm frequently responds to direct intra-arterial vasodilator therapy, which is the only treatment that has been shown to be effective.     

巴曲酶治疗突发性耳聋的疗效观察

目的评价巴曲酶治疗突发性耳聋的效果和安全性。方法对62例突发性耳聋的患者采用常规治疗（低分子右旋糖酐、ATP、辅酶A、地塞米松）。然后采用随机对照试验设计，将62例突发性耳聋的患者分成A、B两组。在常规治疗的基础上，A组28例患者加用巴曲酶治疗，给予巴曲酶10BU加入生理盐水100mL，1h内滴完，隔天5BU一次，3次为一个疗程。B组34例患者用血管扩张剂（疏血通）冶疗，疏血通6mL加入5％葡萄糖静滴，10d为一个疗程。结果A组和B组的总有效率分别为85．7％（24／28）和64．7％（22／34），两组比较差异有显著性（P〈0．05）。结论在常规治疗的基础上加用巴曲酶治疗突发性耳聋疗效优于血管扩张剂，且安全，值得临床推广和应用。     

Catecholamine-induced vasodilator metabolite release from guinea-pig hearts is not due to increased myocardial activity

Guinea-pig isolated hearts were perfused in series, the donor heart perfusate supplying the recipient heart. Isoprenaline increased the rate and force of contraction and oxygen consumption of donor hearts and produced a coronary vasodilatation. This was accompanied by the release of vasodilator metabolite as demonstrated by vasodilatation of the recipient heart, the -adrenoceptors of which were antagonized by propranolol. During arrest of donor hearts by either carbachol or application of a fibrillating current, isoprenaline still released vasodilator metabolite and increased oxygen consumption but without changes in rate or tension. This release was prevented by -adrenoceptor blockade. It is concluded that the sympathomimeticinduced coronary vasodilatation is mediated via the release of a vasoactive metabolite, the trigger for which is not the concomitant mechanical hyperactivity.This work was supported by a Science Research Council CASE award in collaboration with Fisons Pharmaceuticals Ltd., Loughborough, Great Britain     

Pharmacological basis for the use of Borago officinalis in gastrointestinal, respiratory and cardiovascular disorders

AIM OF THE STUDY: In this study, we investigated the crude extract of Borago officinalis leaves (Bo.Cr) for its antispasmodic, bronchodilator, vasodilator and cardio-depressant activities to rationalize some of the traditional uses. MATERIALS AND METHODS: Bo.Cr was studied using different isolated tissue preparations including rabbit jejunum, trachea, aorta, and guinea-pig atria. RESULTS: Bo.Cr which was tested positive for flavonoids, coumarins, sterols and tannins produced a concentration-dependent relaxation of spontaneous and K+ (80mM)-induced contractions in isolated rabbit jejunum preparations, suggestive of Ca++ antagonist effect, which was confirmed when pretreatment of the tissue with Bo.Cr produced a rightward shift in the Ca++ concentration-response curves like that caused by verapamil. In rabbit tracheal preparations, Bo.Cr relaxed the carbachol (1microM) and K+-induced contractions. Verapamil also produced non-specific inhibitory effect. In rabbit aorta preparations, Bo.Cr exhibited vasodilator effect against phenylephrine and K+-induced contractions similar to verapamil. When tested in guinea-pig atria, Bo.Cr caused inhibition of both atrial force and rate of contractions. CONCLUSIONS: These results suggest that the spasmolytic effects of Bo.Cr are mediated possibly through Ca++ antagonist mechanism, which might explain the traditional use of Borago officinalis in hyperactive gastrointestinal, respiratory and cardiovascular disorders.     

硝酸甘油联合阿司匹林治疗心绞痛研究

目的：研究血管扩张剂硝酸甘油联合阿司匹林治疗心绞痛的临床疗效。方法：选择我院2007年2月～2010年3月收治的90例心绞痛患者,随机分为两组,硝酸甘油联合阿司匹林治疗组（A组）45例和硝酸甘油治疗组（B组）45例,两组均给予硝酸甘油和复方丹参注射液或红花注射液静脉滴注。A组在B组的基础上加用阿司匹林,观察药物的治疗疗效和治疗前后心绞痛发作次数、血压、心率变化;并测定用药前后血糖、血脂、心肌酶的改善情况。结果：药物治疗后,A组总有效率为95.56%（43/45）,B组总有效率为84.44%（38/45）,两组差异有统计学意义（χ2=4.38,P〈0.05）;两组治疗后心电图进行比较,A组心电图有效率为97.78%（44/45）,B组为82.22%（37/45）,两组差异有统计学意义（χ2=8.25,P〈0.05）;63例（A组23例,B组40例）患者在服用硝酸甘油后出现头昏、头胀痛、低血压等症状,减少药物剂量后反应消失,未出现严重的副作用。结论：血管扩张剂联合治疗心绞痛能减缓耐药性发生,提高治愈率,值得在临床广泛应用。