bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early carotid atherosclerosis in healthy middle-aged women. A follow-up study.
Authors: Bonithon-Kopp C , Jouven X , Taquet A , Touboul P J , Guize L , Scarabin P Y 
Published: June 2011

Few longitudinal data about early atherosclerotic lesions of the carotid arteries are available in general populations. The main purpose of this study was to investigate risk factors for development and regression of intimal-medial thickening and atheromatous plaques.
Initial and 2-year examinations of the carotid arteries with high-resolution B-mode ultrasonography were performed in 308 apparently healthy women aged 45 to 55 years. The development of new atheromatous plaques and new intimal-medial thickening and the disappearance of preexisting plaques and intimal-medial thickening defined the four outcomes of interest.
The development of plaques occurred more frequently in women with intimal-medial thickening than in women with normal carotid arteries at baseline (14.4% versus 7.2%, P < .053). A regression was seen in 21.7% of the women with preexisting plaques. Development of intimal-medial thickening occurred in 47.5% of the women with normal carotid arteries whereas 20.2% of the women with preexisting intimal-medial thickening showed a regression of their lesions. Multiple logistic regression showed that smoking (regression coefficient +/- SE: 1.281 +/- 0.450; P < .005), baseline levels of systolic blood pressure (regression coefficient +/- SE: 0.031 +/- 0.015; P < .04) and apolipoprotein B (regression coefficient +/- SE: 0.016 +/- 0.007; P < .03) were independently associated with the development of plaques, whereas the presence of an intimal-medial thickening did not reach the significance level (regression coefficient +/- SE: 0.639 +/- 0.436; P < .15). Independent predictors of the development of intimal-medial thickening were age (regression coefficient +/- SE: 0.124 +/- 0.048; P < .04) and, with a borderline significance level, (log)triglycerides (regression coefficient +/- SE: 0.854 +/- 0.451; P < .06). Low levels of low-density lipoprotein cholesterol (regression coefficient +/- SE: 0.027 +/- 0.009; P < .004) were associated with its regression.
This longitudinal study emphasizes the interest of B-mode ultrasonography in the monitoring of early carotid lesions. It gives further support to the hypothesis that intimal-medial thickening may be an early indicator of the atherosclerotic process.
A transpulmonary contrast medium enhances the transcranial Doppler signal in humans.
Authors: Ries F , Honisch C , Lambertz M , Schlief R 
Published: June 2011

Transtemporal insonation in transcranial Doppler sonography is often impaired by an insufficient signal-to-noise ratio, especially in elderly patients. A transpulmonary stable air microbubble suspension was injected intravenously in humans as an intracranial ultrasonic contrast agent.
In a clinical phase II study, 20 patients (15 women, 5 men; mean age, 65.5 +/- 11.5 years) presenting with clinical indications for transcranial Doppler investigation were examined. A total of 97 intravenous injections with different concentrations (200, 300, and 400 mg/mL of suspension) of air microbubbles bound to galactose microparticles as a carrier were performed. The signal enhancement of color-coded pulse curves of basal cerebral arteries was evaluated off-line in comparison to an integrated color-coded decibel scale, considering quality, quantity, and time course of enhancement requiring a 3-dB level above the native signal. The overall diagnostic information was assessed according to a reliability score.
The first acoustic signal increase was registered after an average of 21 seconds. Time intervals for a dose-dependent peak intensity and maximal duration were 41.3 +/- 17.1 seconds and 118.0 +/- 69.8 seconds (200 mg/mL); 55.5 +/- 27.7 seconds and 237.0 +/- 112.3 seconds (300 mg/mL); and 66.1 +/- 31.8 seconds and 293.0 +/- 122.0 seconds (400 mg/mL), respectively. Duration of signal enhancement increased significantly (P < .05) with higher concentrations. The extent of signal enhancement during the whole pulse curve reached an average of 9.1 +/- 5.0 dB for 200 mg/mL, 12.0 +/- 5.4 dB for 300 mg/mL (significant on P < .05 level), and 13.1 +/- 5.6 dB for 400 mg/mL concentration (P = NS). Respective maximal intensity spots reached 17.5 +/- 6.0, 20.7 +/- 5.5, and 22.7 +/- 5.9 dB for increasing concentrations, respectively. Overall visual assessment of enhanced pulse curves for diagnostic reliability showed a sufficient result in 38.1% of all injections with 200 mg/mL, in 88.6% with 300 mg/mL, and in 84.2% with 400 mg/mL concentration. Minimal side effects occurring in 12.4% of all injections were all reversible.
Transpulmonary stable air microbubbles bound to a galactose carrier represent a useful and safe contrast agent in case of an insufficient native signal in transcranial Doppler investigation.
Quantification of ultrasound emboli signals in patients with cardiac and carotid disease.
Authors: Grosset D G , Georgiadis D , Kelman A W , Lees K R 
Published: June 2011

The use of Doppler ultrasound to detect arterial emboli has major implications for the classification and treatment of stroke. Experimental studies indicate that embolic materials produce different ultrasound signals, depending on their acoustic properties. To examine the possibility of characterizing emboli of different sources in the clinical setting, we compared the emboli signals of patients with cardiac embolic sources with those of patients with signals of carotid embolic sources.
Transcranial Doppler monitoring (30 minutes per patient) of the middle cerebral arteries was performed in 80 patients with prosthetic cardiac valves and 20 patients with internal carotid artery stenosis. The signal power of emboli was calculated in relation to the background Doppler signal.
In patients who were embolizing from prosthetic heart valves, the frequency of embolus signals was greater than in patients with carotid stenosis who were embolizing (mean +/- SEM: 58.2 +/- 11 versus 8.2 +/- 3 signals per hour; P < .0001, two-sample t test), and total signal power and duration also were higher (power, 2231 +/- 63 versus 455 +/- 109 power units; duration, 55.9 +/- 0.8 versus 29.9 +/- 1.4 milliseconds; both P < .001). The majority of emboli signals were seen during cardiac systole, especially in patients with carotid stenosis (89% in the first half of the cardiac cycle versus 72% in prosthetic valve patients). In 19 patients with prosthetic valves, embolus signals were also recorded from the anterior cerebral artery; the signal count was not significantly different from the middle cerebral artery (43.2 +/- 12.5 versus 64.3 +/- 16 per hour), but anterior cerebral artery signals were of higher power (3306 +/- 148 versus 2441 +/- 109 power units, P < .001).
There is promise of being able to distinguish emboli on the basis of power measurements. Emboli of different sources (eg, carotid and cardiac) appear to have different ultrasonic characteristics, which are likely to be based on composition and size.
Functional image of dynamic computed tomography in diagnostic and prognostic evaluation of ischemic stroke within the first 6 hours.
Authors: Toriyama T , Tanizaki Y , Hongo K , Osawa M , Kobayashi S 
Published: June 2011

It is important to make a diagnosis before a low-density area appears on computed tomography for appropriate management of acute ischemic stroke. We report the diagnostic and prognostic usefulness of functional image of dynamic computed tomography for acute ischemic stroke.
Forty-seven patients with ischemic strokes within 6 hours of ictus underwent dynamic computed tomography in which functional images were obtained. These findings were compared with angiographic findings, follow-up computed tomography, and clinical outcome.
The functional images were categorized into three groups: (1) cortical type: abnormalities on time to peak image and/or corrected mean transit time image involving mainly cortical structures (29 cases); (2) noncortical type: abnormalities on either or both images limited to noncortical structures (7 cases); and (3) normal type: no abnormalities on both images (11 cases). Cortical type as a diagnostic test for arterial trunk occlusion had a good sensitivity (100%), specificity (95%), and accuracy (98%). Infarction volume on follow-up computed tomography correlated with extension of prolonged time-to-peak area (r = .80, P < .01) and that of prolonged corrected mean transit time area (r = .81, P < .01). Cortical type was associated with significantly unfavorable outcome (P < .01).
Functional image of dynamic computed tomography findings predicted arterial trunk occlusion, infarction volume, and clinical outcome. Therefore, this technique would be useful not only for indicating definitive angiography and subsequent therapy but for evaluating the effectiveness of surgical or medical recanalization.
Smooth muscle cell proliferation and localization of macrophages and T cells in the occlusive intracranial major arteries in moyamoya disease.
Authors: Masuda J , Ogata J , Yutani C 
Published: June 2011

Stenosis or occlusion due to fibrocellular intimal thickening in the intracranial major arteries is thought to be the primary lesion in moyamoya disease, but its etiology and pathogenesis are unknown. The present study was designed to analyze cellular components of the lesions and their pathological process.
Stenotic or occlusive intracranial arterial lesions were collected from six autopsied patients who died of moyamoya disease. The cellular components were analyzed by immunohistochemical staining using cell-type-specific monoclonal antibodies. The sections were also immunostained for proliferating cell nuclear antigen (PCNA) to detect proliferating cells and for two different types of intermediate filaments, desmin and vimentin, to evaluate phenotypes of the intimal smooth muscle cells.
The thickened intima was composed predominantly of smooth muscle cells with an admixture of some macrophages and T cells. Macrophages and T cells were scattered in the superficial layer of the intimal thickening, and these were occasionally associated with organization of fibrin thrombi. Proliferating smooth muscle cells, indicated by PCNA-positive nuclei and muscle actin-positive cytoplasm, were found in the thickened intima in four patients. Immunohistochemical staining for intermediate filaments revealed intimal smooth muscle cells showing positive staining for vimentin and negative staining for desmin, compatible with the phenotype of synthetic smooth muscle cells.
The present study provides evidence that smooth muscle cells are proliferating in the occlusive lesions in intracranial major arteries in moyamoya disease. The colocalization of inflammatory cells and PCNA-positive cells suggests that inflammatory stimuli may induce proliferative response of smooth muscle and contribute to the formation of the intracranial occlusive lesions in moyamoya disease.
Blood pressure after stroke. A one-year follow-up study.
Authors: Carlsson A , Britton M 
Published: June 2011

Blood pressure changes in the year after acute stroke have been poorly documented.
We therefore studied blood pressure for 1 year after discharge from the hospital in 226 consecutive patients (mean age, 73 years) surviving an acute stroke.
Marked increases (p < 0.001) in mean systolic and mean diastolic blood pressures were seen in two thirds (69%) of the patients 1 month after discharge, and blood pressure remained stable at this level during the remainder of the follow-up year. Similar blood pressure changes were seen irrespective of sex, final stroke diagnosis, or whether the patient had a history of hypertension before the stroke. Patients with a history of hypertension had significantly higher blood pressures (p < 0.001) throughout the follow-up year than previously normotensive patients. One month after discharge blood pressure was found to have decreased in 31% of the patients; these were older and had a higher mortality during the follow-up year than patients with blood pressure increases. About 20% of all patients suffered from orthostatism (defined as a decrease in systolic blood pressure of > or = 20 mm Hg when rising from the supine position to standing).
We conclude that antihypertensive treatment should not be reduced before discharge from the hospital and that blood pressure should be checked about 1 month after discharge. We suggest that standing blood pressure also be measured to make an appropriate treatment decision.
Leukocyte infiltration in acute hemispheric ischemic stroke.
Authors: Wang P Y , Kao C H , Mui M Y , Wang S J 
Published: June 2011

The dynamics of leukocyte infiltration in human cerebral ischemia were studied using technetium-99m hexamethylpropyleneamine oxime (99mTc HMPAO)-labeled leukocyte brain single-photon emission computed tomography (SPECT).
Twenty-two patients diagnosed as having hemispheric ischemic stroke were examined with 99mTc HMPAO brain SPECT for cerebral blood flow study and 99mTc HMPAO-labeled leukocyte brain SPECT for the study of leukocyte infiltration. Three patients with chronic hemispheric ischemic stroke received one examination. Nineteen patients with acute hemispheric ischemic stroke received their initial examination within the first after onset. Follow-up examinations were performed at intervals of 1-3 weeks whenever possible.
In patients with chronic hemispheric ischemic stroke, leukocyte infiltration was not seen in areas of perfusion defect. In patients with acute hemispheric ischemic stroke, leukocyte infiltration was seen in areas of perfusion defect during the acute stage, which persisted for no less than 5 weeks after onset and then declined.
A new method to study and monitor the process of leukocyte infiltration in acute cerebral ischemia using 99mTc HMPAO-labeled leukocyte brain SPECT is described. This method shows that leukocyte infiltration in acute hemispheric ischemic stroke is a dynamic process that persists for no less than 5 weeks and then declines.
Age as a modifying factor on the effect of antihypertensive therapy in focal stroke in rats.
Authors: Slivka A 
Published: June 2011

Antihypertensive treatment with hydralazine for 10 weeks but not 6 weeks reduces infarct size in 13-week-old spontaneously hypertensive rats subjected to focal cerebral ischemia. This study was designed to examine whether the duration of treatment needed to reduce infarct size depends on how long hypertension is present before the initiation of antihypertensive therapy.
Six-week-old spontaneously hypertensive rats were treated for 6 weeks and 10-month-old spontaneously hypertensive rats for 10 weeks with 20 mg/kg hydralazine added daily to the drinking water. The animals were then subjected to focal cerebral ischemia by tandem permanent common carotid and middle cerebral artery occlusion.
Blood pressure in the treated groups was lower than that in the untreated groups for the entire treatment period in both experiments. Infarct volume in 10-month-old spontaneously hypertensive rats treated for 10 weeks, but not in 6-week-old spontaneously hypertensive rats treated for 6 weeks, was significantly less than in untreated controls (p = 0.02).
This study emphasizes the importance of duration of antihypertensive treatment in reducing infarct volume in spontaneously hypertensive rats after focal cerebral ischemia and demonstrates that the effect appears to be independent of the duration of hypertension before the initiation of treatment.
Prophylactic effect of imidapril on stroke in stroke-prone spontaneously hypertensive rats.
Authors: Ogiku N , Sumikawa H , Hashimoto Y , Ishida R 
Published: June 2011

It has been reported that some angiotensin converting enzyme inhibitors can prevent stroke-prone spontaneously hypertensive rats from stroke at much higher doses than clinical doses used for hypertension therapy. This study was performed to investigate the prophylactic effectiveness of imidapril against stroke in comparison with enalapril.
Salt-loaded stroke-prone spontaneously hypertensive rats were orally given imidapril (0.5, 1, 2, and 5 mg/kg per day), enalapril (2 and 5 mg/kg per day), or hydralazine (5 mg/kg per day). Stroke signs were scored, and blood pressure, protein concentration, and N-acetyl-beta-D-glucosaminidase activity in urine were measured. After 2 weeks of medication, angiotensin converting enzyme activities in the aorta were measured 24 hours after dosing.
In the control group, severe hypertension developed, and all rats died within 12 weeks because of stroke. Imidapril and enalapril dose-dependently decreased the stroke-related mortality, and both agents at 5 mg/kg per day showed excellent prophylaxis, although they did not inhibit hypertensive development. Imidapril at 0.5 mg/kg per day significantly prevented stroke to almost the same extent as enalapril at 2 mg/kg per day or hydralazine at 5 mg/kg per day. Imidapril dose-dependently suppressed the elevation of the two urinary indexes, which was followed by stroke. Imidapril inhibited enzyme activity in the aorta more strongly than did enalapril at the same dose.
Imidapril prevented the incidence of stroke in stroke-prone spontaneously hypertensive rats at a dose of 0.5 mg/kg per day or more by amelioration of kidney dysfunction. Reduction of blood pressure is not necessary, although enzyme inhibition in the vasculature may partly relate to the effect.
Spatial features of focal infarction after hydralazine treatment in stroke-prone spontaneously hypertensive rats.
Authors: Coyle P , Feng X 
Published: June 2011

Rapid occlusion of the middle cerebral artery above the rhinal fissure produces a large ischemic infarct in hypertensive rats, but this occlusion results in a minimal lesion in young normotensive rats. Our purpose was to attenuate rising blood pressure in young stroke-prone spontaneously hypertensive rats with hydralazine before the occlusion to determine if the gross infarct volume is smaller, and if it is, to determine whether length, width, depth, or surface area of the infarct changes, which could suggest a mechanism of protection.
Untreated rats (n = 6) and rats receiving hydralazine for 1.5 (n = 6) or 5 (n = 5) weeks were anesthetized, and the middle cerebral artery was rapidly occluded with a ligature. One day later the rats were killed and the brains were fixed in formalin. Fine-grain-release film that is sensitive to spectral properties of the infarct was used to photograph the tissue. Infarcted areas were traced on paper and then digitized for measurements and computations with a microcomputer.
Compared with untreated rats, tail systolic blood pressure (120 +/- 3 versus 138 +/- 4 mm Hg), infarct volume (61 +/- 4 versus 93 +/- 6 mm3), infarct surface area (39 +/- 1 versus 54 +/- 2 mm2), infarct width (3.8 +/- 0.1 versus 4.8 +/- 0.2 mm), and infarct length (6.0 +/- 0.3 versus 8.1 +/- 0.3 mm) were less in rats receiving hydralazine for 5 weeks (p < 0.05). No change was detected in infarct depth.
Treatment of young stroke-prone spontaneously hypertensive rats with hydralazine for 5 weeks before middle cerebral artery occlusion results in a smaller infarct. The narrower, shorter dimensions indicate increased protection against lateral enlargement of the infarct and the possibility that protection was due to increased collateral blood flow through modified blood vessels.
A new approach to the integrity of dual blood-brain barrier functions of global ischemic rats. Barrier and carrier functions.
Authors: Yoshizumi H , Fujibayashi Y , Kikuchi H 
Published: June 2011

We studied the influence of reperfusion on carrier and barrier functions of the blood-brain barrier after transient global ischemia in rats.
We used iodine-125-labeled 3-iodo-alpha-methyl-L-tyrosine and carbon-14-labeled sucrose as tracers for studying carrier and barrier functions of the blood-brain barrier, respectively. Brain uptakes of these two tracers were measured in Wistar rats subjected to either 15- or 30-minute four-vessel occlusion developed by Pulsinelli and Brierly before recirculation for 3, 6, 24, 48, and 72 hours. Tracer (5 microCi) was injected intravenously in each rat 30 minutes before killing the animal.
Following 15- or 30-minute ischemia, [14C]sucrose uptakes were significantly higher at 3 and 6 hours of reperfusion before recovery to control values after reperfusing for 24 to 48 hours in almost all brain regions. However, a rebound in radioligand uptake was significantly manifested in some sites at 72 hours after reperfusion (p < 0.05 to p < 0.01). Uptakes of 125I-3-iodo-alpha-methyl-L-tyrosine were brain site-dependent: significantly (p < 0.05) higher in cortex (3 and 48 hours after reperfusion) and thalamus (3, 6, and 48 hours after reperfusion) but significantly (p < 0.05 to p < 0.01) lower in striatum, cortex (72 hours after reperfusion), and midbrain (6, 24, and 72 hours after reperfusion). Because the [14C]sucrose uptake in brain was 10% lower than that of 125I-3-iodo-alpha-methyl-L-tyrosine, the change in absolute transport of the latter tracer was approximated to its brain uptake.
The carrier and barrier functions of the blood-brain barrier should be evaluated separately. The radioligand 125I-3-iodo-alpha-methyl-L-tyrosine may serve as a useful tool to evaluate the carrier function of the blood-brain barrier after transient cerebral ischemia in rats.
Role of transcranial Doppler in neuroradiological treatment of intracranial vasospasm.
Authors: Hurst R W , Schnee C , Raps E C , Farber R , Flamm E S 
Published: June 2011

The expanded role of interventional neuroradiological treatment for post-subarachnoid hemorrhage vasospasm has highlighted the diagnostic utility of transcranial Doppler studies in this condition. The role of transcranial Doppler in follow-up and determining the need for repeat intervention has not been previously emphasized.
Intracranial angioplasty for clinically evident vasospasm after subarachnoid hemorrhage was performed in four patients. In two patients, transcranial Doppler flow velocities remained elevated despite initial anatomic correction of the vasospasm. Reangiography revealed new areas of involvement by vasospasm. Reangioplasty or papaverine infusion treatment of the new lesions resulted in decreased flow velocities and clinical improvement in all patients.
Transcranial Doppler has a more significant role than has been previously emphasized in the management of patients undergoing interventional neuroradiological treatment for intracranial vasospasm. Specifically, the persistence of elevated transcranial Doppler flow velocities after intracranial angioplasty suggests the need for repeat angiographic evaluation and possibly further therapy.