Evaluation of cerebral hemodynamics by transcranial Doppler ultrasonography in carotid endarterectomy

The authors studied the linear blood flow rate (LBFR) in the middle cerebral artery (MCA) which was measured by means of transcranial dopplerography during carotid endarterectomy in 25 patients. Analysis of the results showed that the changes of LBFR in the MCA correlate with alterations in blood pressure: LBFR in the MCA reduced most during compression of the common carotid artery in patients with considerable affection of the contralateral carotid artery. The maximal increase of the blood flow during compression of the common carotid artery occurred when the initial LBFR in the MCA was lowest. After the blood flow in the common carotid artery is restored the LBFR in the MCA is determined by the degree of stenosis of the artery which is operated on and the degree of collateral circulation. The method makes it possible to determine in time the need for additional measures of protection of the brain from ischemia.     

Add-on angiotensin receptor blockade with maximized ACE inhibition

BACKGROUND: Prolonged angiotensin-converting enzyme (ACE) inhibitor therapy leads to angiotensin I (Ang I) accumulation, which may "escape" ACE inhibition, generate Ang II, stimulate the Ang II subtype 1 (AT1) receptor, and exert deleterious renal effects in patients with chronic renal diseases. We tested the hypothesis that losartan therapy added to a background of chronic (>3 months) maximal ACE inhibitor therapy (lisinopril 40 mg q.d.) will result in additional Ang II antagonism in patients with proteinuric chronic renal failure with hypertension. METHODS: Sixteen patients with proteinuric moderately advanced chronic renal failure completed a two-period, crossover, randomized controlled trial. Each period was one month with a two-week washout between periods. In one period, patients received lisinopril 40 mg q.d. along with other antihypertensive therapy, and in the other, losartan 50 mg q.d. was added to the previously mentioned regimen. Hemodynamic measurements included ambulatory blood pressure monitoring (ABP; Spacelabs 90207), glomerular filtration rate (GFR) with iothalamate clearances and cardiac outputs by acetylene helium rebreathing technique. Supine plasma renin activity and plasma aldosterone and 24-hour urine protein were measured in all patients. RESULTS: Twelve patients had diabetic nephropathy, and four had chronic glomerulonephritis. The mean age (+/- SD) was 53 +/- 9 years. The body mass index was 38 +/- 5.7 kg/m(2), and all except two patients were males. Seated cuff blood pressure was 156 +/- 18/88 +/- 12 mm Hg. The pulse rate was 77 +/- 11 per min, and the cardiac index was 2.9 +/- 0.5 L/min/m(2). Mean log 24-hour protein excretion/g creatinine or overall ABPs did not change. Mean placebo subtracted, losartan-attributable change in protein excretion was +1% (95% CI, -20% to 28%, P = 0.89). Similarly, the change in systolic ambulatory blood pressure (ABP) was 4.6 mm Hg (-5.7 to 14.9, P = 0.95), and diastolic ABP was 1.5 mm Hg (-4.5 to 7.6, P = 0.59). No change was seen in cardiac output. However, there was a mean 14% increase (95% CI, 3 to 26%, P = 0.017) in GFR attributable to losartan therapy. A concomitant fall in plasma renin activity by 32% was seen (95% CI, -15%, - 45%, P = 0.002). No hyperkalemia, hypotension, or acute renal failure occurred in the trial. These results were not attributable to sequence or carryover effects. CONCLUSIONS: Add-on losartan therapy did not improve proteinuria or ABP over one month of add on therapy. Improvement of GFR and fall in plasma renin activity suggest that renal hemodynamic and endocrine changes are more sensitive measures of AT1 receptor blockade. Whether add-on AT1 receptor blockade causes antiproteinuric effects or long-term renal protection requires larger and longer prospective, randomized controlled trials.     

Evaluation of tubulointerstitial injury by Doppler ultrasonography in glomerular diseases

AIMS: While Doppler ultrasonography is used commonly in various renal diseases, its clinical value in diagnosis of renal parenchymal diseases, especially glomerular diseases, remains controversial. We investigated whether Doppler ultrasonography in glomerular diseases could discriminate tubulointerstitial lesions, which correlated closely with long-term prognosis for renal function. METHODS: Sixty patients with primary or secondary glomerular diseases were examined by Doppler ultrasonography immediately before renal biopsy. The resistive index was calculated, as was the atrophic index (a newly proposed parameter defined as renal sinus length/renal length). These were compared with histologic changes in biopsy specimens. RESULTS: Receiver operator characteristic analysis showed a resistive index of 0.65 to be the optimal for discriminating tubulointerstitial changes with specificity of 100% and sensitivity of 57.1%. Tubulointerstitial injury scores were significantly higher in patients with resistive indices exceeding 0.65 than in patients with a lower value. An atrophic index of 0.70 was also shown to be optimal with specificity 100% and sensitivity 61.9%. In combination, the 2 indices showed improved sensitivity; when the patients were divided into groups where both resistive and atrophic indices were normal (respectively < or = 0.65 and < or = 0.70) or where either or both were high, sensitivity rose to 85.7%, while specificity remained 94.4%. CONCLUSIONS: In combination, the resistive and atrophic indices discriminated tubulointerstitial injury in glomerular diseases with high specificity and sensitivity.     

NF-kappaB-dependent increase in intrarenal angiotensin II induced by proteinuria

BACKGROUND: Intrarenal activation of the renin-angiotensin system has been suggested to play a pivotal role in the progression of various renal diseases, but the regulation of each component has not been fully clarified. We investigated the roles of nuclear factor kappaB (NF-kappaB) activation in the intrarenal renin-angiotensin system changes induced by proteinuria. METHODS: We used unilaterally nephrectomized rats loaded with bovine serum albumin as a model of proteinuric renal injury. Renal NF-kappaB activation was inhibited by gene transfer of the truncated form of IkappaBalpha via injection of a recombinant adenovirus vector into the renal artery, as we reported previously. RESULTS: Inhibition of renal NF-kappaB activation attenuated the increases in intrarenal angiotensinogen protein (2.0-fold in rats with protein overloading and saline injection to 1.3-fold in rats with protein overloading and injection of a truncated form of IkappaBalpha) and angiotensin II (1.8-fold to 1.2-fold), and angiotensinogen mRNA. The increases in angiotensin-converting enzyme (ACE) and angiotensin II receptor type 2 were unaffected by NF-kappaB inhibition. The expression of ACE2, an enzyme that metabolizes angiotensins I and II, was decreased by 37%, and NF-kappaB inhibition abolished the decrease. Immunohistochemical analysis revealed that the angiotensinogen and ACE2 expression changes occurred mainly in proximal tubule cells (i.e., the target of adenoviral gene transfer). CONCLUSION: These results indicate that proteinuria induces an increase in renal angiotensin II in an NF-kappaB-dependent manner. Induction of angiotensinogen and decrease in ACE2 levels may be involved in this NF-kappaB-dependent increase in angiotensin II.     

Evaluation of preoperative effect for rectal cancer by transrectal ultrasonography

The ultrasonographic examination was applied for the purpose of volume estimation of rectal cancer. We have performed 15 cases of echographic volume estimation compared with that of resected specimen (control group) and mean volume estimation error rate was 14.6% between two methods. And we also performed 17 preoperative irradiation cases of rectal cancer. Each tumor volume of pre- and post-irradiation was estimated echogenically and was compared with that of resected specimen. In the case when irradiation effect was remarkable, estimated volume by ultrasonography was much smaller in post-irradiation compared with that of pre-irradiation. Same tendency was also recognized in the study of resected specimen. Histopathological irradiation effect was also highly recognized in the case when echographic diminished rate was prominent. This method will useful for the judgement of preoperative irradiation effect in rectal cancer.     

Restoration of cardiomyocyte functional properties by angiotensin II receptor blockade in diabetic rats

Recent evidence suggests that blockade of the renin-angiotensin system ameliorates diabetes-induced cardiac dysfunction, but the mechanisms involved in this process remain elusive. We investigated the effect of treatment with an angiotensin II receptor blocker, losartan, on the metabolic and electrophysiological properties of cardiomyocytes isolated from streptozotocin-induced diabetic (STZ) rats. Glucose uptake and electrophysiological properties were measured in ventricular cardiomyocytes from normoglycemic and STZ-induced diabetic rats given vehicle or 20 mg x kg(-1) x day(-1) losartan for 8 weeks. Insulin and beta-adrenergic stimulation failed to increase the glucose uptake rate in STZ cardiomyocytes, whereas the alpha-adrenergic effect persisted. Concurrently, a typical prolongation of action potential duration (APD) and a decrease of transient outward current (I(to)) were recorded in patch-clamped STZ myocytes. Treatment with losartan did not affect body weight or glycemia of diabetic or control animals. However, in losartan-treated STZ-induced diabetic rats, beta-adrenergic-mediated enhancement of glucose uptake was completely recovered. APD and I(to) were similar to those measured in losartan-treated control rats. A significant (P < 0.0001) correlation between metabolic and electrophysiological parameters was found in control, diabetic, and losartan-treated diabetic rats. Thus, angiotensin receptor blockade protects the heart from the development of cellular alterations typically associated with diabetes. These data suggest that angiotensin receptor blockers may represent a new therapeutic strategy for diabetic cardiomyopathy.     

Evaluation of posttraumatic cerebral blood flow velocities by transcranial Doppler ultrasonography

Thirty-five patients were admitted to the hospital with Glasgow coma scale scores of 4 to 7 after severe, blunt head injury. Blood flow velocities of the middle cerebral artery (MCA) and the ipsilateral internal carotid artery (ICA), high in the neck, were recorded noninvasively by Doppler ultrasonography. Serial examinations were begun within 48 hours of trauma and continued until the patient either died or was discharged. Spasm of the MCA was assumed if the ratio of the velocity of blood flow in the MCA (VMCA) to the velocity of blood flow in the ICA (VICA) exceeded 3 (normal value, 1.7 +/- 0.4). In cases of severe MCA spasm, this ratio is higher because of increased flow velocity in the MCA and reduced flow in the ICA due to increased cerebrovascular resistance. Higher MCA velocities with VMCA/VICA above 3, consistent with MCA spasm, were found in 14 of the 35 patients (40%). The increase began as early as 48 hours after injury, reached a maximum between Days 5 and 7, and lasted until 2 weeks after injury. There was a significant correlation between the occurrence of vasospasm and the quantity of cisternal or intracerebral blood seen on a computed tomographic scan. No correlation was found with the age of the patients, the Glasgow coma scale score at admission, the intracranial pressure, or the functional outcome 6 months after injury. The occurrence of a secondary infarction in a patient with severe MCA spasm suggests that, at least in some cases, spasm may influence the prognosis.     

Effects of angiotensin type-I receptor blockade on pericardial fibrosis.

BACKGROUND: Reoperative cardiac surgical procedures are associated with a significantly greater complication rate than that of the initial procedure. Enhanced collagen synthesis can occur due to increased production of angiotensin II (Ang-II) and subsequent activation of Ang AT(1) receptor. Accordingly, the goal of the current study is to test the hypothesis that increased Ang AT(1) receptor activity following pericardiotomy contributes to pericardial thickening and fibrosis. MATERIALS AND METHODS: Adult pigs were randomly assigned to three protocols: (1) pericardiotomy with 28-day recovery period (n = 5); (2) pericardiotomy with Ang AT(1) receptor blockade instituted throughout the 28-day recovery period using 60 mg/day valsartan (n = 5); and (3) sham controls (n = 6). Pericardium samples were collected and analyzed by biochemical and histomorphometrical methods. Pericardial fibrosis occurred postpericardiotomy as indicated by increased hydroxyproline content from normal value of 50 +/- 3 microg/mg to 75 +/- 4 microg/mg (P < 0. 05). RESULTS: Pericardial thickness was increased postpericardiotomy to 2.7 +/- 0.4 mm compared to normal values of 0.4 +/- 0.05 mm (P < 0.05). Ang AT(1) receptor blockade reduced pericardial thickness by 50% and the relative degree of fibrosis was comparable to that of the normal group. CONCLUSIONS: The results from this pericardial fibrosis animal model suggest that Ang AT(1) receptor activation contributes to the development of pericardial thickening and collagen accumulation in the postoperative period. Thus, Ang AT(1) receptor inhibition may provide a novel therapeutic strategy to prevent pericardial fibrosis that follows cardiac surgical procedures.     

应用彩色多普勒超声评价颈动脉内膜切除术

目的探讨二维超声和CDFI技术在颈动脉内膜切除术（CEA）术前诊断及术后疗效评价中的应用价值。方法应用二维超声和CDFI于CEA术前、术后对比观察66例颈动脉狭窄患者的血管内径、狭窄率及血流动力学参数,将术前超声检出结果与DSA结果进行对照。结果术前超声检出6例颈动脉狭窄60%～69%,53例狭窄70%～99%,7例颈动脉闭塞,与DSA相比,超声诊断准确率为95.45%（63/66）。CEA术后狭窄处颈动脉内径显著增宽,血流速度明显下降,血流动力学参数较术前有明显改善（P均〈0.001）。术后随访效果满意。结论彩色多普勒超声对颈动脉狭窄的诊断率较高,能客观反映治疗前后血流动力学改变,在CEA术前筛查诊断及术后疗效评价中均具有重要应用价值。     

Better renoprotective effect of angiotensin II antagonist compared to dihydropyridine calcium channel blocker in childhood

BACKGROUND: The dihydropyridine calcium channel blocker amlodipine and the angiotensin II antagonist irbesartan effectively reduce blood pressure in hypertensive children. METHODS: Eligible for the open-label, randomized study were nephropathic children between 6.0 and 18 years of age with plasma creatinine <177 micromol/L, overt proteinuria, untreated arterial hypertension (systolic, 5 to 30 mm Hg; and diastolic, 1 to 15 mm Hg;>95th centile) and stable immunosuppressive treatment. The initial dose of amlodipine was 5 mg (body weight, 20 to 40 kg) and 10 mg (body weight,>40 kg), respectively, that of irbesartan, which was 75 mg (body weight, 20 to 40 kg) and 150 mg (body weight,>40 kg), respectively. The dosage was doubled if necessary. RESULTS: A total of 26 children aged 6.1 to 17 years were allocated to receive either amlodipine (N = 13) or irbesartan (N = 13) for 16 weeks. Severe edema and headache occurred in two patients on amlodipine who withdrew from the study. No adverse experiences were noted in patients given irbesartan. Amlodipine [by 12 (10 to 14)/7 (5 to 10) mm Hg; median and interquartile range, respectively] and irbesartan [by 13 (9 to 16)/9 (7 to 11) mm Hg, respectively] reduced blood pressure (P < 0.01) in a similar fashion. Heart rate, plasma sodium, and creatinine did not change. Irbesartan slightly increased plasma potassium [by 0.1 (0.0 to 0.2) mmol/L; P < 0.05]. Plasma albumin and the urinary albumin/creatinine ratio were similar before and with amlodipine. On the contrary, irbesartan increased plasma albumin [by 4 (3 to 5) g/L; P < 0.03] and decreased the urinary albumin/creatinine ratio [by 242 (68 to 312) mg/mmol; P < 0.03]. CONCLUSION: The study demonstrates that in children the effect of angiotensin II antagonists on proteinuria is better than that of dihydropyridine calcium channel blockers.     

A comparison of duplex Doppler ultrasonography and intrarenal manometry in the diagnosis of acute renal transplant rejection

Renal transplant rejection is frequently difficult to differentiate from other causes of renal dysfunction. This study examined the use of duplex Doppler ultrasound and intrarenal manometry in a consecutive series of 73 patients who underwent renal transplantation. Altogether 327 duplex scans were analyzed and, for each, a resistive index (RI) was calculated. A raised RI predicted rejection in patients with grafts that functioned immediately, but not in those that had delayed function. A rise in intrarenal pressure ( greater than or equal to 40 mmHg) indicated the presence of rejection in both groups. However, neither test had a sensitivity of more than 71% and this was not improved by combining the results of the two tests for each patient. Although both tests have a place in transplantation, renal biopsies may still be required to confirm rejection.     

Evaluation of pancreatic allograft circulation using color Doppler ultrasonography

In conclusion, color flow Doppler ultrasonography is a safe, noninvasive method to study perfusion in the pancreatic allograft. In trained hands, reproducibly quantitative measurements can be made of the circulation in the transplanted pancreatic allograft. With further experience, it is our hope that spectral analysis will elucidate rejection as it has for us with kidney transplants. Because the technique is noninvasive, it has a high degree of patient acceptance.     

经阴道彩色多普勒超声综合评价体外受精-胚胎移植中子宫内膜容受性的研究进展

子宫内膜容受性是决定胚胎着床的关键因素之一。用于评价子宫内膜容受性的方法很多,但目前尚缺乏评价内膜容受性的可靠标准。经阴道彩色多普勒超声以其具有简便、无创、形态结合血流测定、可重复等优点为临床评估子宫内膜容受性提供了一个新手段。为了探讨其在预测子宫内膜容受性的价值,本文对近年来经阴道彩色多普勒超声在子宫内膜形态、子宫血流灌注、子宫收缩性、子宫内膜波状运动等的临床应用做一综述。     

彩色多普勒超声评估雷诺现象患者掌指动脉血流参数变化

目的探讨彩色多普勒超声评估雷诺现象患者掌浅弓动脉、指掌侧固有动脉病变的应用价值。方法采用彩色多普勒超声对病例组42例雷诺现象患者的左侧掌浅弓动脉、左侧中指指掌侧固有动脉进行检查,记录血管走行、血流充盈情况及血流动力学参数:收缩期峰值血流速度(PSV)、舒张末期血流速度(EDV)、阻力指数(RI)、搏动指数(PI)。对照组为35名接受体检的正常健康成人,分别测量上述各参数,比较病例组和对照组各参数的差异。结果病例组患者左侧掌浅弓动血流充盈尚可,彩色血流显示率为100%(42/42),左侧中指指掌侧固有动脉血流充盈差,血管变细、甚至闭塞,血管彩色血流示率为92.86%(39/42)。与对照组相比,病例组患者左侧中指指掌侧固有动脉PSV、EDV和左侧掌浅弓动脉EDV减低,RI、PI均增高,比较差异均有统计学意义(P均0.05);病例组左侧掌浅弓动脉PSV较对照组减低,差异无统计学意义(P0.05)。结论彩色多普勒超声能够评估雷诺现象患者指掌侧固有动脉、掌浅弓动脉血流动力学改变,可为雷诺现象的诊断、治疗提供有效依据。     

Improving renoprotective effects by adding piperazine ferulate and angiotensin receptor blocker in diabetic nephropathy: a meta-analysis of randomized controlled trials

International Urology and Nephrology - Piperazine ferulate, a derivative of ferulic acid has been widely used in clinical practice for cardiovascular and kidney diseases in China. The objective of...     

Additive effect of ACE inhibition and angiotensin II receptor blockade in type I diabetic patients with diabetic nephropathy

Albuminuria and hypertension are predictors of poor renal and cardiovascular outcome in diabetic patients. This study tested whether dual blockade of the renin-angiotensin system (RAS) with both an angiotensin-converting enzyme (ACE) inhibitor (ACE-I) and an Angiotensin-II receptor blocker (ARB) is superior to either drug alone in type I diabetic patients with diabetic nephropathy (DN). A randomized double-blind crossover trial was performed with 8-wk treatment with placebo, 20 mg of benazepril once daily, 80 mg of valsartan once daily, and the combination of 20 mg of benazepril and 80 mg of valsartan. Twenty type I diabetic patients with DN were included. At the end of each treatment period, albuminuria, 24-h BP, and GFR were measured. Eighteen patients completed the study. Placebo values were: albuminuria [mean (95% CI)], 701 (490 to 1002) mg/24 h; BP [mean (SEM)], 144 (4)/79 (2) mmHg, and GFR [mean (SEM)], 82 (7) ml/min per 1.73 m(2). Treatment with benazepril, valsartan, or dual blockade significantly reduced albuminuria and BP compared with placebo. Benazepril and valsartan were equally effective. Dual blockade induced an additional reduction in albuminuria of 43 % (29 to 54 %) compared with any type of monotherapy, and a reduction in systolic BP of 6 (0 to 13) mmHg and 7 (1 to 14) mmHg (versus benazepril and valsartan, respectively) and a reduction of 7 (4 to 10) mmHg diastolic compared with both monotherapies. GFR was reversibly reduced on dual blockade compared with monotherapy and placebo. All treatments were safe and well tolerated. In conclusion, dual blockade of the RAS may offer additional renal and cardiovascular protection in type I diabetic patients with DN.     

彩色多普勒超声诊断肾内静脉血栓形成1例

患者，男，15岁，主因“2天前无明显诱因出现发热，最高达39.4℃，左侧腰背部阵发性绞痛，拒按，伴血尿”来我院就诊。既往于4年前患有“肾病综合征”，治疗后好转。查体：腹膨降，软，左上腹压痛，反跳痛，左季肋区疼痛，拒按，左肾区叩痛，肠鸣音正常，双下肢对称性可凹陷性水肿。实验室检查：血常规：