bluuebunny/crossref_metadata_2025 huggingface dataset:
Vasopressin-Induced Protein Kinase C–Dependent Superoxide Generation Contributes to ATP-Sensitive Potassium Channel but Not Calcium-Sensitive Potassium Channel Function Impairment After Brain Injury
Authors: Armstead William M.
Published: June 2011

Background and Purpose
—Pial artery dilation in response to activators of the ATP-sensitive K
+
(K
ATP
) and calcium-sensitive K
+
(K
Ca
) channels is impaired after fluid percussion brain injury (FPI). Vasopressin, when coadministered with the K
ATP
and K
Ca
channel agonists cromakalim and NS1619 in a concentration approximating that observed in cerebrospinal fluid (CSF) after FPI, blunted K
ATP
and K
Ca
channel–mediated vasodilation. Vasopressin also contributes to impaired K
ATP
and K
Ca
channel vasodilation after FPI. In addition, protein kinase C (PKC) activation generates superoxide anion (O
2
−
), which in turn contributes to K
ATP
channel impairment after FPI. We tested whether vasopressin generates O
2
−
in a protein kinase C (PKC)-dependent manner, which could link vasopressin release to impaired K
ATP
and K
Ca
channel–induced pial artery dilation after FPI.

Methods
—Injury of moderate severity (1.9 to 2.1 atm) was produced with the lateral FPI technique in anesthetized newborn pigs equipped with a closed cranial window. Superoxide dismutase–inhibitable nitroblue tetrazolium (NBT) reduction was determined as an index of O
2
−
generation.

Results
—Under sham injury conditions, topical vasopressin (40 pg/mL, the concentration present in CSF after FPI) increased superoxide dismutase–inhibitable NBT reduction from 1±1 to 23±4 pmol/mm
2
. Chelerythrine (10
−7
mol/L, a PKC inhibitor) blunted such NBT reduction (1±1 to 9±2 pmol/mm
2
), whereas the vasopressin antagonist l-(β-mercapto-β,β-cyclopentamethylene propionic acid)2-(
o
-methyl)-Tyr-arginine vasopressin (MEAVP) blocked NBT reduction. Chelerythrine and MEAVP also blunted the NBT reduction observed after FPI (1±1 to 15±1, 1±1 to 4±1, and 1±1 to 5±1 pmol/mm
2
for sham-, chelerythrine-, and MEAVP-treated animals, respectively). Under sham injury conditions, vasopressin (40 pg/mL) coadministered with cromakalim or NS1619 blunted dilation in response to these K
+
channel agonists, whereas chelerythrine partially restored such impaired vasodilation for cromakalim but not NS1619. Cromakalim- and NS1619-induced pial artery dilation also was blunted after FPI. MEAVP partially protected dilation to both K
+
channel agonists after FPI, whereas chelerythrine did so for only cromakalim responses (for cromakalim at 10
−8
and 10
−6
mol/L, 13±1% and 23±1%, 2±1% and 5±1%, 9±1% and 15±2%, and 9±1% and 16±2% for sham-, FPI-, FPI-MEAVP–, and FPI-chelerythrine–pretreated animals, respectively).

Conclusions
—These data show that vasopressin, in concentrations present in CSF after FPI, increased O
2
−
production in a PKC-dependent manner and contributes to such production after FPI. These data show that vasopressin contributes to K
ATP
but not K
Ca
channel function impairment in a PKC-dependent manner after FPI and suggest that vasopressin contributes to K
Ca
channel function impairment after FPI via a mechanism independent of PKC activation.
Clinically Unidentified Dissection of Vertebral Artery as a Cause of Cerebellar Infarction
Authors: Iwase Hirotaro , Kobayashi Masahiko , Kurata Atsushi , Inoue Shinya
Published: June 2011

Background and Purpose
—Dissection of vertebral arteries has been reported in association with minor neck movements without signs of trauma on the surface of the neck. In addition, injury of a vertebral artery can cause brain infarctions. However, few cases have been reported in which fatal brain infarction was due to nonocclusive, clinically undetected, traumatic thrombus formation in a vertebral artery.

Case Description
—A 62-year-old man was hit by a car, and a right cerebellar infarction was found the day after the accident. The cause of the infarction could not be detected by angiography. Although the patient recovered favorably after surgical removal of the right lateral hemisphere of the cerebellum, he died suddenly 2 weeks after the accident. An autopsy and a microscopic study revealed pulmonary thromboembolism and organizing traumatic lesions of the right vertebral artery without occlusion or noteworthy stenosis of the artery.

Conclusions
—We concluded that the patient sustained traumatic lesions of the right vertebral artery during the traffic accident 2 weeks before death and that his cerebellar infarction was due to a thrombus resulting from these traumatic lesions.
Accuracy of In Vivo Carotid B-Mode Ultrasound Compared With Pathological Analysis
Authors: Schulte-Altedorneburg Gernot , Droste Dirk W. , Felszeghy Szabolcs , Kellermann Mónika , Popa Vasile , Hegedüs Katalin , Hegedüs Csaba , Schmid Martina , Módis László , Ringelstein E. Bernd , Csiba László
Published: June 2011

Background and Purpose
—This study aimed to determine the correlation of in vivo ultrasound measurements of intima-media thickening (IMT), lumen diameter, and cross-sectional area of the common carotid artery (CCA) with corresponding measurements obtained by gross pathology and histology.

Methods
—Sixty-six moribund neurological patients (mean age 71 years) underwent B-mode ultrasound of the CCA a few days before death. During autopsy, carotid specimens were removed in toto. Carotid arteries were ligated and cannulated for injection of a hydrophilic embedding material under standardized conditions. The carotid bifurcation was frozen and cut manually in 3-mm cross slices. Digital image analysis was carried out to determine the diameter and the cross-sectional area of the frozen slices of the CCA. IMT was assessed by light microscope. Ultrasonic and planimetric data were compared.

Results
—Mean measurements of lumen diameter and cross-sectional area were 7.13±1.27 mm and 0.496±0.167 cm
2
, respectively, by ultrasound, and 7.81±1.45 mm and 0.516±0.194 cm
2
, respectively, by planimetric analysis of the unfixed redistended carotid arteries (
R
2
=0.389 and 0.497). The mean IMT was 1.005±0.267 mm by ultrasound and 0.67±0.141 mm histologically, resulting in a mean difference of −31%.

Conclusions
—Transcutaneous B-mode ultrasound provides a reliable approach for in vivo measurements of the cross-sectional area and, less exactly, of the lumen diameter of the CCA. Compared with histological results, in vivo ultrasound measurements of the IMT are systematically larger.
Angiotensin-Converting Enzyme Inhibition With Enalapril Slows Progressive Intima-Media Thickening of the Common Carotid Artery in Patients With Non–Insulin-Dependent Diabetes Mellitus
Authors: Hosomi Naohisa , Mizushige Katsufumi , Ohyama Hideo , Takahashi Tsutomu , Kitadai Masaya , Hatanaka Yoshio , Matsuo Hirohide , Kohno Masakazu , Koziol James A.
Published: June 2011

Background and Purpose
—Whether angiotensin-converting enzyme (ACE) inhibitors have any clinically significant antiatherogenic effects in humans remains unproven. We undertook a prospective randomized clinical trial of 98 patients with non–insulin-dependent diabetes mellitus (NIDDM) to examine the efficacy of ACE inhibition with enalapril for preventing intima-media (IM) thickening of the carotid wall as measured ultrasonographically.

Methods
—Ninety-eight NIDDM patients were randomly assigned either to enalapril at 10 mg/d (n=48) or to a control group (n=50); the planned duration of the trial was 2 years. All patients were seen at baseline (study entry) and 2 subsequent formal annual evaluations, in addition to standard clinical management for NIDDM. IM thickening and vascular lumen diameters were determined for all patients on the basis of baseline and 2 subsequent annual evaluations with carotid ultrasonography. We performed an intent-to-treat analysis to assess changes in IM thickening over the course of the study.

Results
—Annual IM thickening measurements of the right and left common carotid arteries were 0.01±0.02 and 0.01±0.02 mm/y in the enalapril-treated group and 0.02±0.03 and 0.02±0.02 mm/y in the control group, respectively (
P
<0.05). From regression analysis, annual IM thickening was found to be predicted by enalapril use, sex, and insulin use (F
3,94
=3.86,
P
=0.012). When we controlled for these other variables, enalapril use reduced annual IM thickening of right and left common carotid arteries by 0.01±0.004 mm/y relative to the control group over the course of this study.

Conclusions
—Long-term treatment with an ACE inhibitor (enalapril) slows progressive IM thickening of the common carotid artery in NIDDM patients.
Enhanced Endothelium-Dependent Vasodilation in Fabry Disease
Authors: Altarescu Gheona , Moore David F. , Pursley Randall , Campia Umberto , Goldstein Seth , Bryant Melissa , Panza Julio A. , Schiffmann Raphael
Published: June 2011

Background and Purpose
—Fabry disease is an X-linked lysosomal storage disease secondary to deficiency of α-galactosidase A with resulting glycolipid accumulation, particularly globotriaosylceramide in arterial smooth muscle and endothelial cells. A systemic vasculopathy, including early-onset stroke, is prevalent without a clear pathogenesis.

Methods
—Seventeen normotensive and normocholesterolemic hemizygous Fabry patients (aged 21 to 49 years) and 13 control subjects (aged 21 to 48 years) were investigated by venous plethysmography, allowing assessment of forearm blood flow. Plethysmographic measurements were obtained at baseline and during intra-arterial infusion of acetylcholine and sodium nitroprusside both with and without
N
G
-monomethyl-
l
-arginine (L-NMMA).

Results
—Forearm blood flow was significantly higher in patients than in control subjects at all 3 acetylcholine doses (
P
=0.014). Patients had a greater response to acetylcholine even after the addition of L-NMMA (
P
=0.036).

Conclusions
—These results demonstrate an increased endothelium-mediated vascular reactivity in Fabry disease. The increased vessel response to acetylcholine with and without L-NMMA suggests altered functionality of non-NO endothelium-dependent vasodilatory pathways.
Cerebral Vasoreactivity and Internal Carotid Artery Flow Help to Identify Patients at Risk for Hyperperfusion After Carotid Endarterectomy
Authors: Hosoda Kohkichi , Kawaguchi Tetsuro , Shibata Yuji , Kamei Masahito , Kidoguchi Keiji , Koyama Junji , Fujita Shigekiyo , Tamaki Norihiko
Published: June 2011

Background and Purpose
—Hyperperfusion syndrome is a rare but potentially devastating complication after carotid endarterectomy (CEA). The aim of this study was to investigate whether preoperative measurement of cerebral vasoreactivity (CVR) and intraoperative measurement of internal carotid artery (ICA) flow could identify patients at risk for hyperperfusion after CEA.

Methods
—For 26 patients with unilateral ICA stenosis ≥70%, cerebral blood flow (CBF) and CVR were investigated before and 1 month after CEA, with resting and acetazolamide-challenge single-photon emission CT. CBF on the first postoperative day was also measured. ICA flow was measured before and after reconstruction by electromagnetic flowmeter during surgery.

Results
—Ipsilateral CBF on the first postoperative day significantly increased relatively (56.6±53.2%) as well as absolutely (37.9±8.8 to 57.7±18.0 mL/100 g per minute) in the reduced CVR group (CVR <12%) but not in the normal CVR group (CVR ≥12%) (10.3±15.5% and 40.6±7.9 to 43.9±5.7 mL/100 g per minute, respectively). One month later, this difference almost disappeared. Two patients showed ipsilateral CBF increase of ≥100%. A significant association of intracerebral steal with hyperperfusion (CBF increase ≥100%) on the first postoperative day was also observed. ICA flow increase after reconstruction significantly correlated with CBF increase on the first postoperative day in the reduced CVR group but not in the normal CVR group. The threshold of ICA flow increase for hyperperfusion was estimated to be 330 mL/min in the reduced CVR group.

Conclusions
—Single-photon emission CT with acetazolamide challenge and ICA flow measurement during surgery could identify patients at risk for hyperperfusion after CEA, in whom careful monitoring and control of blood pressure should be initiated even intraoperatively.
Prospective Value of Perfusion and X-Ray Attenuation Imaging With Single-Photon Emission and Transmission Computed Tomography in Acute Cerebral Ischemia
Authors: Barthel Henryk , Hesse Swen , Dannenberg Claudia , Rössler Annegret , Schneider Dietmar , Knapp Wolfram H. , Dietrich Jürgen , Berrouschot Jörg
Published: June 2011

Background and Purpose
—The aim of the present study was to test the hypothesis that perfusion single-photon emission computed tomography (SPECT), carried out in addition to transmission computed tomography (TCT), improves the predictive value of brain imaging within the therapeutically relevant time window after acute cerebral ischemia.

Methods
—Using TCT and [
99m
Tc]ethyl cysteinate dimer (ECD)-SPECT within 6 hours after symptom onset, we examined 108 patients (44 women, 64 men; mean age 65±13 years) with acute ischemic stroke attributed to the territory of the middle cerebral artery (MCA). In each case, 3 experts prospectively evaluated the early SPECT and TCT images. We correlated these ratings with follow-up TCT findings for the final infarction as well as with clinical outcome (Scandinavian Stroke Scale, Barthel Index, Modified Rankin Scale) after 30 and 90 days.

Results
—Severe activity deficits on SPECT, not caused by local atrophy on TCT, were the best predictors (positive predictive value [PPV ]94%, 95% CI 89% to 99%; negative predictive value [NPV] 90%, 95% CI 78% to 100%;
P
<0.001) for evolving cerebral infarction. Complete MCA infarctions were predicted with significantly higher accuracy with early SPECT (area under receiver operating characteristic curve [AUC] index 0.91) compared with early TCT (AUC index 0.77) and clinical parameters (AUC index 0.73,
P
<0.05). Logistic regression analysis revealed 1 independent predictor for completed MCA territory infarction: SPECT activity deficits in the corresponding areas (PPV 88%, 95% CI 65% to 100%; NPV 96%, 95% CI 92% to 100%;
P
<0.001). Furthermore, death after stroke was optimally predicted by [
99m
Tc]ECD-SPECT. Clinical outcome up to 90 days after the stroke event best correlated with the degree of activity deficits in early SPECT (
r
=0.53,
P
<0.001).

Conclusions
—[
99m
Tc]ECD brain perfusion SPECT that completes TCT definitely improves the predictive value of brain imaging after acute cerebral ischemia. Thus, the combined imaging of brain edema and of cerebral perfusion early after stroke is recommended for clinical use.
Effect of Paracetamol (Acetaminophen) on Body Temperature in Acute Ischemic Stroke
Authors: Dippel D. W.J. , van Breda E. J. , van Gemert H. M.A. , van der Worp H. B. , Meijer R. J. , Kappelle L. J. , Koudstaal P. J.
Published: June 2011

Background and Purpose
—Body temperature is a strong predictor of outcome in acute stroke. However, it is unknown whether antipyretic treatment leads to early and clinically worthwhile reduction of body temperature in patients with acute stroke, especially when they have no fever. The main purpose of this trial was to study whether early treatment of acute ischemic stroke patients with acetaminophen (paracetamol) reduces body temperature.

Methods
—Seventy-five patients with acute ischemic stroke confined to the anterior circulation were randomized to treatment with either 500 mg (low dose) or 1000 mg (high dose) acetaminophen or with placebo, administered as suppositories 6 times daily during 5 days. Body temperatures were measured with a rectal electronic thermometer at the start of treatment and after 24 hours and with an infrared tympanic thermometer at 2-hour intervals during the first 24 hours and at 6-hour intervals thereafter. The primary outcome measure was rectal temperature at 24 hours after the start of treatment.

Results
—Treatment with high-dose acetaminophen resulted in 0.4°C lower body temperatures than placebo treatment at 24 hours (95% CI 0.1°C to 0.7°C). The mean reduction from baseline temperature with high-dose acetaminophen was 0.3°C (95% CI 0°C to 0.6°C) higher than that in placebo-treated patients. Treatment with low-dose acetaminophen did not result in lower body temperatures. After 5 days of treatment, no differences in temperature were found between the placebo and the high- or low-dose acetaminophen groups.

Conclusions
—Treatment with a daily dose of 6000 mg acetaminophen may result in a small, but potentially beneficial, decrease in body temperature shortly after ischemic stroke, even in normothermic and subfebrile patients. Further studies should determine whether this effect is reproducible and whether early reduction of body temperature leads to improved outcome.
Lipoprotein(a) and Cognitive Performances in an Elderly White Population
Authors: Sarti Cristina , Pantoni Leonardo , Pracucci Giovanni , Di Carlo Antonio , Vanni Paola , Inzitari Domenico
Published: June 2011

Background and Purpose
—Elevated lipoprotein(a) [Lp(a)] serum levels have been associated with an increased risk of vascular diseases, and preliminary observations suggest that they are a risk factor for vascular dementia. The relationship between Lp(a) levels and cognitive performances in the general population has never been investigated. Our aim was to evaluate the effect of elevated Lp(a) levels on cognitive functions in the elderly.

Methods
—Cognitive performances were assessed by means of the Mini-Mental State Examination (MMSE), the Babcock Short Story, and the Matrix Test in a population sample of 435 white subjects aged 65 to 84 years who were evaluated at baseline and after 3 years. Lp(a) levels were determined by ELISA.

Results
—No statistically significant difference was found in neuropsychological test scores between subjects with and without elevated Lp(a) levels, although subjects with elevated Lp(a) levels had slightly better cognitive performances. This difference reached a statistical significance level only in a subscore of the Matrix Test (number of correct responses) when adjusted for age, sex, education, smoking, and history of stroke. At follow-up, no statistically significant difference was found in cognitive performances between subjects with and without elevated Lp(a) serum levels in either univariate or multivariate analyses. Subjects with and without elevated Lp(a) showed a similar decline rate during follow-up.

Conclusions
—In this sample of elderly white subjects, elevated Lp(a) levels were not associated with poorer cognitive performances or with an increased rate of cognitive decline. Elevated Lp(a) levels do not appear to be a major determinant of cognitive impairment in the elderly.
Adaptive Behavior in Stressful Situations and Stroke Incidence in Hypertensive Men
Authors: André-Petersson Lena , Engström Gunnar , Hagberg Bo , Janzon Lars , Steen Gunilla
Published: June 2011

Background and Purpose

—

Although hypertension is a major risk factor for stroke, many hypertensive persons remain healthy. The aim of the present study was to analyze whether adaptation in a stressful situation was associated with the incidence of stroke in hypertensive men.

Methods

—

Two hundred thirty-eight hypertensive men were followed from baseline in 1982/1983 until first stroke, death, or December 31, 1996. Adaptation to stress was studied with the serial Color-Word Test. In the Regression dimension, 4 patterns of adaptation could be distinguished according to mastering of the test. Successful mastering of the test was shown in stabilized patterns, increasing difficulty in cumulative patterns, fluctuating difficulty in dissociative patterns, and fluctuating difficulty that increased during testing in cumulative-dissociative patterns. The patterns were compared regarding stroke incidence.

Results

—

Forty-three men experienced a stroke during follow-up. Stroke rates per 1000 person-years were 12.6 for men with stabilized patterns, 14.3 for men with cumulative patterns, 16.2 for men with dissociative patterns, and 31.2 for men with cumulative-dissociative patterns. Multivariate analysis, adjusted for relevant cerebrovascular risk factors, showed that the cumulative-dissociative pattern of the Regression dimension was associated with an increased risk of stroke during follow-up (relative risk 3.00, 95% CI 1.32 to 6.81).

Conclusions

—

The specific behavior pattern, characterized by the greatest difficulties in managing the test, was associated with incidence of stroke in hypertensive men. One interpretation is that hypertensive men who chronically fail to find successful strategies in stressful situations are vulnerable to the damaging effects of stress and thereby at an increased risk of a future stroke.
Matrix Metalloproteinase Expression After Human Cardioembolic Stroke
Authors: Montaner Joan , Alvarez-Sabín José , Molina Carlos , Anglés Ana , Abilleira Sonia , Arenillas Juan , González Miguel Angel , Monasterio Jasone
Published: June 2011

Background and Purpose

—

Uncontrolled expression of matrix metalloproteinases (MMPs) can result in tissue injury and inflammation. In animal models of cerebral ischemia, the expression of MMP-2 and MMP-9 was significantly increased. However, their role in human stroke in vivo remains unknown. Therefore, we sought to determine the temporal profile of MMP expression in patients with acute ischemic stroke and to investigate its relationship to stroke severity, location of arterial occlusion, and total infarct volume.

Methods

—

Serial MMP-2 and MMP-9 determinations were made in 39 patients with cardioembolic strokes that involved the middle cerebral artery territory by means of enzyme-linked immunosorbent assay. Blood samples, transcranial Doppler recordings, and National Institutes of Health Stroke Scale (NIHSS) scores were obtained at baseline and at 12, 24, and 48 hours after stroke onset. Infarct volume was measured with CT scanning at 48 hours.

Results

—

No correlation was found between MMP-2 and NIHSS score at any time point, although a close relation appeared between mean MMP-9 and final NIHSS score (
r
=0.486,
P
=0.002). MMP-9 value was the only factor associated with the final NIHSS score in the multiple logistic regression model (OR 4.54, 95% CI 1.5 to 13.75). A cut-point of MMP-9 142.18 ng/mL had a positive predictive value of 94.4% to assess a patient’s NIHSS (<8 or ≥8) by the end of the study. Final MMP-2 and MMP-9 levels were significantly lower when recanalization occurred (528±144.3 versus 681.4±239.2 ng/mL,
P
=0.031 for MMP-2; 110.2±100.9 versus 244.8±130 ng/mL,
P
=0.004 for MMP-9). A positive correlation was found between mean MMP-9 and infarct volume (
r
=0.385,
P
=0.022).

Conclusions

—

MMPs are involved in the acute phase of human ischemic stroke. MMP-9 levels are associated with neurological deficit, middle cerebral artery occlusion, and infarct volume.
Difference in Carotid Artery Wall Structure Between Swedish and French Men at Low and High Coronary Risk
Authors: Denarié Nicolas , Simon Alain , Chironi Gilles , Gariepy Jérôme , Kumlin Lars , Massonneau Marc , Lanoiselée Catherine , Dimberg Lennart , Levenson Jaime
Published: June 2011

Background and Purpose

—

We attempted to detect a group-specific north-south difference in carotid artery intima-media thickness (IMT), a marker of subsequent cardiovascular complication, by means of a case (high risk)–control (low risk) study in French and Swedish men.

Methods

—

The selection of high-risk and low-risk subjects was performed within the lower and upper percentiles of the Framingham risk distribution of 2 samples of 1000 white, male auto workers (45 to 50 years of age) in France (Renault) and Sweden (Volvo). In total, 299 men at low risk (79 French, 76 Swedish) and high risk (61 French, 83 Swedish), free from sustained hypertension, definite hypercholesterolemia, and cardiovascular disease, were included. Both common carotid arteries, by ultrasonography and central off-line computerized analysis, provided measurements of far wall media thickness, lumen diameter, and cross-sectional area IMT (CSA-IMT).

Results

—

As compared with low-risk status, high-risk status was associated with higher IMT (
P
<0.001), diameter (
P
<0.01), and CSA-IMT (
P
<0.001) in French men and higher CSA-IMT (
P
<0.05) in Swedish men. IMT, diameter, and CSA-IMT were higher in Swedish than in French men in the low-risk group (
P
<0.001) and in the high-risk group (
P
<0.01,
P
<0.001,
P
<0.001). The multivariate analysis of the whole population showed that IMT, diameter, and CSA-IMT were associated with risk status (
P
<0.01,
P
<0.01,
P
<0.001) and geographic status (
P
<0.001).

Conclusions

—

These findings show that the geographic status influences carotid artery structure independent of traditional cardiovascular risk factors and that this may affect the mortality and morbidity gradient between Northern and Southern Europe.
Open-Label Dose-Titration Safety and Efficacy Study of Tizanidine Hydrochloride in the Treatment of Spasticity Associated With Chronic Stroke
Authors: Gelber David A. , Good David C. , Dromerick Alexander , Sergay Stephen , Richardson Melissa
Published: June 2011

Background and Purpose

—

Spasticity is a frequently observed motor impairment that develops after stroke; it can cause pain and disability in those affected. The objective of the present study was to evaluate the safety and efficacy of tizanidine, a centrally acting α
2
-adrenergic agonist, in the treatment of stroke-related spasticity.

Methods

—

Forty-seven patients, who were a minimum of 6 months poststroke and had significant spasticity, were studied at 4 centers. Tizanidine was administered in an open-label manner for 16 weeks, beginning at 2 mg/d and slowly titrated to a maximum of 36 mg/d. The Modified Ashworth Scale, muscle strength testing, functional assessments, and Pain and Functional Spasticity Questionnaires were administered at baseline and at 4, 8, 16, and 18 weeks (after 1 week off tizanidine).

Results

—

Spasticity was significantly improved between baseline and week 16, with a decrease in total upper extremity Modified Ashworth Scale score of 2.80±0.47 (
P
<0.0001). No decline in strength was noted. Treatment with tizanidine resulted in a significant improvement in pain intensity (
P
=0.0375), quality of life (
P
=0.0001), and physician assessment of disability (
P
=0.0001). The most frequent side effects were somnolence (62%) and dizziness (32%). No serious adverse events were considered to be drug related. Ten of 47 patients (21%) were able to reach the maximum daily dosage of 36 mg.

Conclusions

—

Overall, the data suggest that tizanidine is safe and efficacious in the treatment of stroke-related spasticity, preserving muscle strength while reducing muscle tone and painful spasms in affected patients.
Predictive Value of Neurochemical Monitoring in Large Middle Cerebral Artery Infarction
Authors: Schneweis Susanne , Grond Martin , Staub Frank , Brinker Gerit , Neveling Michael , Dohmen Christian , Graf Rudolf , Heiss Wolf-Dieter
Published: June 2011

Background and Purpose

—

Space-occupying brain edema is a life-threatening complication in patients with large hemispheric stroke. Early identification of patients at risk is necessary to decide on invasive therapies such as decompressive hemicraniectomy or hypothermia. To assess potential predictors of malignant brain edema by measurement of intracranial pressure (ICP) and microdialysis in patients with large hemispheric stroke and different clinical course.

Methods

—

In an ongoing prospective clinical study, an ICP and microdialysis probe were placed into the parenchyma of the ipsilateral frontal lobe of 10 patients. Extracellular concentrations of glutamate, lactate, pyruvate, and glycerol were measured continuously. Repeated cranial CT scans were scrutinized for size of infarction and presence of mass effect.

Results

—

The dynamics of the different substances varied in accordance with the clinical course, size of infarction, and local brain edema: Increase in ICP and in glutamate concentration and lactate-pyruvate ratio was followed by massive edema and large infarcts; generally low and stable ICP and substrate concentrations were found in patients without progressive space-occupying infarcts.

Conclusions

—

In patients with large hemispheric infarction, bedside monitoring with microdialysis is feasible and might be helpful together with ICP recording to follow the development of malignant brain edema.
Effect of Trunk Restraint on the Recovery of Reaching Movements in Hemiparetic Patients
Authors: Michaelsen Stella M. , Luta Anamaria , Roby-Brami Agnès , Levin Mindy F.
Published: June 2011

Background and Purpose
—

Reaching movements made with the affected arm in hemiparetic patients are often accompanied by compensatory trunk or shoulder girdle movements, which extend the reach of the arm. We investigated the effects of the suppression of these compensatory movements on reaching ability in hemiparetic individuals.

Methods
—

Eleven healthy and 11 hemiparetic individuals participated. Three-dimensional kinematic analysis was used to quantify reaches made to a close and a distant target (near the limit of arm’s length). Unrestrained reaches were compared with those in which shoulder girdle and trunk movements were restrained by a harness.

Results
—

During unrestrained reaching, abnormal trunk recruitment and limitations in elbow and shoulder movements were correlated with the degree of clinical stroke severity (
r
=−0.91 to −0.96) in hemiparetic patients. During trunk restraint, ranges of elbow and shoulder joint movement increased in both groups. In addition, elbow and shoulder interjoint coordination improved. This was caused by increases in the range of joint motion as well as by a better dynamic temporal relation between joints.

Conclusions
—

Trunk restraint allowed patients with hemiparetic stroke to make use of arm joint ranges that are present but not normally recruited during unrestrained arm-reaching tasks. Thus, the underlying “normal” patterns of movement coordination may not be entirely lost after stroke. Appropriate treatments, such as trunk restraint, may be effective in uncovering latent movement patterns to maximize arm recovery in hemiparetic patients.
Neurogenesis by Progenitor Cells in the Ischemic Adult Rat Hippocampus
Authors: Yagita Yoshiki , Kitagawa Kazuo , Ohtsuki Toshiho , Takasawa Ken-ichiro , Miyata Takaki , Okano Hideyuki , Hori Masatsugu , Matsumoto Masayasu
Published: June 2011

Background and Purpose

—

Recently, there has been great interest in adult neurogenesis. We investigated whether transient forebrain ischemia could influence the proliferation of neuronal progenitor in the subgranular zone (SGZ) of the rat hippocampus and whether aging could influence the neurogenesis after ischemia.

Methods

—

Male Wistar rats were subjected to 4-vessel occlusion model. We used a bromodeoxyuridine (BrdU) labeling method to identify the postproliferation cells and double-immunostaining with confocal microscopy to determine the cell phenotype.

Results

—

The number of BrdU-positive cells in the SGZ increased ≈5.7-fold 8 days after ischemia, compared with the control. BrdU-positive cells formed clusters, which suggested that these cells had divided from an original progenitor cell, and expressed Musashi1 (Msi1), a marker of neural stem/progenitor cells. Although astrocytes also expressed Msi1 in the adult brain, Msi1-positive cells that formed clusters in the SGZ did not express glial fibrillary acidic protein, an astrocyte marker. About 70% of all BrdU-positive cells in the SGZ represented the neuronal phenotype 4 weeks after the BrdU injection. Although proliferation of progenitor cells was stimulated in both young and older animals, aging accelerated the reduction in newborn cells after ischemia.

Conclusions

—

Our results indicate that ischemic stress stimulated the proliferation of neuronal progenitor cells in the SGZ of both young and old rats but resulted in increased neurogenesis only in young animals. Our findings will be important in developing therapeutic intervention to enhance endogenous neurogenesis after brain injury.
Knowledge of Stroke Risk Factors, Warning Symptoms, and Treatment Among an Australian Urban Population
Authors: Sug Yoon Sung , Heller Richard F. , Levi Christopher , Wiggers John , Fitzgerald Patrick E.
Published: June 2011

Background and Purpose—

Reduction in the risk of stroke and increase in the speed of hospital presentation after the onset of stroke both depend on the level of knowledge of stroke in the general population. The aim of the present study was to assess baseline knowledge regarding stroke risk factors, symptoms, treatment, and information resources.

Methods—

A community-based telephone interview survey was conducted in the Newcastle urban area in Australia. A total of 1278 potential participants between the ages of 18 to 80 were selected at random from an electronic telephone directory. A trained telephone interviewer conducted a telephone survey using the Computer-Assisted Telephone Interviewing (CATI) program.

Results—

A total of 822 participants completed the telephone interview. Six hundred three participants (73.4%) correctly identified the brain as the affected organ in stroke. The most common risk factors for stroke identified by respondents were smoking (identified by 324 [39.4%]) and stress (identified by 277 [33.7%]). The most common warning sign of stroke described by respondents was “blurred and double vision or loss of vision in an eye,” listed by 198 (24.1%). A total of 626 (76.2%) respondents correctly listed ≥1 established stroke risk factor, but only 409 (49.8%) respondents correctly listed ≥1 warning sign.

Conclusions—

The level of knowledge in the community of established stroke risk factors, warning signs, and treatment as indicated by this survey suggests that a community-based education program to increase public knowledge of stroke may contribute to reducing the risk of stroke and to increasing the speed of hospital presentation after the onset of stroke.
Report of the Joint Committee for Stroke Facilities
Authors: FIELDS WILLIAM S. , BELL RODERIC M. , ELLINGSON ROBERT J. , GARRETT H. EDWARD , GOLDBERG HERBERT I. , JANEWAY RICHARD , MIALE AUGUST , SCHECHTER MANNIE M. , SWEET WILLIAM H. , VAN DYK HENRY J. L. , WALTZ ARTHUR G.
Published: June 2011

The use of special procedures and equipment has become an integral, progressively complex, and increasingly expensive part of diagnosis and management in cerebrovascular disease. However, tests have enhanced rather than replaced the role of precise neurological examination and sound clinical judgment in caring for the stroke patient. The physician is obligated to understand the nature, limitations, complications, costs, indications, contraindications, and values of the many available diagnostic modalities and to avoid their indiscriminate use; most, and in some cases all, of this information should be known as well by hospital administrators, nurses, allied health professionals, and even the patient and his family. This Section discusses the present status of radiological and other diagnostic studies in disorders of the cerebral circulation. Rapid changes are occurring in this field with the almost daily appearance of new procedures, modifications, and applications, thus increasing the responsibility of all concerned to keep current with these new developments.
Effects of Blood Gases on the Pressure-Flow Relationships in Canine Cerebral Circulation
Authors: IWABUCHI TAKAYUKI , KUTSUZAWA TAKASHI , IKEDA KYUHEI , NAKAMURA TAKASHI
Published: June 2011

The effects of the arterial oxygen saturation and carbon dioxide pressure on the pressure-flow relationships in cerebral circulation were studied in 22 dogs. The cerebral blood flow was observed with stepwise lowering of the systemic arterial blood pressure by controlled bleeding in normoxic normocapnic, normoxic hypocapnic, normoxic hypercapnic, hypoxic hypocapnic and hypoxic normocapnic animals. The autoregulation of cerebral blood flow occurred in the animals in which the arterial oxygen saturation and carbon dioxide pressure were above 90%, and between 20 and 46 mm Hg, respectively.

When the arterial oxygen saturation and carbon dioxide pressure were maintained between 17% and 40%, and 34 and 47.5 mm Hg, or above 92%, and between 65 and 82 mm Hg, respectively, almost complete loss of autoregulation was observed. However, autoregulation revived in breathing air at about 30 minutes after autoregulation had been lost during severe hypoxia or hypercapnia, which was induced for about 30 minutes. This suggests that a hypoxic or hypercapnic situation for about 30 minutes does not irreversibly damage the autoregulatory mechanism.
EEG and Arteriographical Findings in Carotid Artery Transient Ischemic Attacks (TIAs)
Authors: WOOLSEY ROBERT M. , HAMBROOK GEORGE W.
Published: June 2011

Thirty patients over 35 years of age with one or more episodes of carotid TIA lasting less than one hour were studied. No patient had a history of brain disease and each had an EEG followed by an arteriogram. Arteriographical study showed 15 patients to have occlusive disease of the internal carotid artery, and four of these had intracranial occlusive arterial disease as well. An additional three patients had only intracranial occlusive arterial disease. Twelve patients had normal arteriographical studies. The EEGs of nine patients were diffusely or focally slow. Twenty-one patients had normal records. Six of the nine patients with abnormal EEGs had arteriographical evidence of intracranial occlusive arterial disease. Only one patient with extracranial carotid stenosis alone showed an EEG abnormality. In two patients with an abnormal EEG the arteriogram was completely normal or showed insignificant change. These data indicate that the EEG has the capacity to reflect changes in cerebral function not clinically evident in patients with carotid TIAs. Such changes were present in almost one-third of the patients in this study. Most commonly, generalized or focal EEG slowing in patients with the clinical syndrome of carotid TIA is associated with the presence of intracranial occlusive arterial disease. Alternatively, the finding of a normal EEG in such patients would suggest the absence of intracranial occlusive arterial disease, but occurs with equal frequency in patients with stenosis of neck vessels and in patients with no arteriographically demonstrable lesion.
Report of the Joint Committee for Stroke Facilities
Authors: TOOLE JAMES F. , TRUSCOTT B. LIONEL , ANDERSON WILLIAM W. , ARONSON PHILIP R. , BLAISDELL WILLIAM , DUSTAN HARRIET P , DYKEN MARK L. , FOLEY ARCHIE R. , HALSEY JAMES H. , LANGFITT THOMAS W. , LAWRENCE MONTAGUE S. , MULLAN JOHN F.
Published: June 2011

Because it contains material concerned with the many critical problems of diagnosis, differential diagnosis, and treatment which arise when a patient presents with a possible stroke, Medical and Surgical Management is one of the most important Sections to appear in this series of publications from the Joint Committee for Stroke Facilities. Practical aspects of the management of transient ischemic attacks (TIA), strokes-inevolution, completed strokes, and the comatose patient are discussed in detail, and attempts made to distinguish between ischemic and hemorrhagic stroke. Recommendations of the study group are listed.
The Epidemiology of Stroke in Central Harlem
Authors: BRUUN BERTEL , RICHTER RALPH W.
Published: June 2011

In January, 1971, the Regional Medical Program of New York implemented a comprehensive regional stroke program at Harlem Hospital in cooperation with Columbia University, New York, New York. The program is directed toward prevention, treatment and rehabilitation of stroke patients. During the first year of the program, 395 patients with the diagnosis of acute stroke were admitted. Sixty-seven had not suffered an acute stroke. Of the remaining 328 patients with a verified acute stroke, 52 were classified as hemorrhagic. Only three patients with TIA were seen. One hundred thirteen patients, 40 of whom had suffered hemorrhagic strokes, died while in the hospital. Two hundred thirty-six patients had associated diseases, hypertension being the most common. The median age was 65 for women and 66 for men. Based on the 1970 census, the rate per 100,000 is estimated to be at least 212. Age-specific rates show a higher than expected rate among the younger age groups. Compared with similar studies of white populations, this study indicates the following characteristics of the entity stroke in an urban black community: (1) incidence is high, (2) patients are relatively young, and (3) high incidence of associated disease.
Cerebral Anoxia: An Improved In Vitro Model for Biochemical Study
Authors: YANAGIHARA TAKEHIKO
Published: June 2011

A previously described in vitro model for cerebral anoxia has been modified to ensure vitality of the rabbit brain slices. The oxygen or nitrogen atmosphere was provided by a continuous gas flow system. Amino acid incorporation into proteins was studied during recovery periods up to 60 minutes. An initial decrease of incorporation and subsequent recovery were observed after an anoxic period of five minutes. On the other hand, a marked decrease and only partial recovery were seen after anoxic periods of 15 minutes or longer. No consistent change was observed in acid-soluble radioactivity. This in vitro model appears to be feasible for various biochemical studies of cerebral anoxia.
The Syndrome of Latent Cerebral Venous Thrombosis: Its Frequency and Relation to Age and Congestive Heart Failure
Authors: TOWBIN ABRAHAM
Published: June 2011

The present investigation indicates the high incidence of intracranial venous thrombosis in adults in the older age groups, especially in the female. Commonly overlooked clinically and pathologically, cerebral venous thrombosis is usually preceded congestive circulatory failure and other related systemic disturbances. Most patients with venous thrombosis intracranially also develop thromboembolic complications at other sites in the body. Although often latent clinically, concurrent pulmonary embolism (as revealed in postmortem studies) occurs in a majority of patients with cerebral venous thrombosis. With clinical and pathological aspects of the process correlated, cerebral venous thrombosis in the aged presents a characteristic pattern. In some cases, in patients with enigmatic progressive coma and neurological deterioration, cerebral venous thrombosis occurs as the primary cause of death. In other instances, in patients with cardiac disease or other major systemic disorders, intracranial venous thrombosis develops as a terminal complication leading to death. Cerebral venous thrombosis is of increasing incidence. There is an expressed need that this form of stroke be more widely recognized clinically.
Dexamethasone as Treatment in Cerebrovascular Disease. 1. A Controlled Study in Intracerebral Hemorrhage
Authors: TELLEZ HENRY , BAUER RAYMOND B.
Published: June 2011

Dexamethasone and a placebo were compared as treatment for 40 patients with intracerebral hemorrhage. Of 19 patients receiving dexamethasone, 17 (89.5%) died during their hospital admission. Of 21 patients receiving a placebo, 16 (76.2%) died. The mortality rate was 100% in 15 patients in the dexamethasone-treated group who were in coma or deep stupor on admission, and the mortality rate was 92% in 12 patients with similar levels of consciousness who received a placebo.

Several parameters of the neurological examination showed an improved quality of survival in the Decadron®-treated group, but this was found only at certain days in the study. No overall statistically significant difference was found between the two therapies.
The Relationship of Regional Cerebrovascular CO
2
Reactivity to Blood Pressure and Regional Resting Flow
Authors: ACKERMAN ROBERT H.
Published: June 2011

Cerebrovascular CO
2
reactivity (the change in cerebral blood flow per mm Hg change in Pa

co

co
2

) is shown to be directly related to resting flow and inversely related to blood pressure for regional as well as for mean CBF data. Both regional and mean CO
2
reactivity therefore are proportional to the ratio resting flow/blood pressure. This ratio is the reciprocal of resistance and may be called
conductance
. When regional CO
2
reactivity for 428 cerebral areas is plotted against an approximation of regional conductance, the data describe positive linear relationships similar to those found when mean CO
2
, reactivity is plotted against mean conductance. These relationships can be demonstrated whether CO
2
reactivity is calculated with specific or percent change in flow, the data describe positive linear lerationships similar to those found when mean CO
2
basal tone of the cerebrovascular bed. The way in which CO
2
reactivity relates to conductance, therefore, may be a more reliable index of the integrity of the cerebrovascular CO
2
response than the CBF change per se. Analysis of CO
2
reactivity as a function of conductance may facilitate the interpretation of mean and regional CO
2
reactivity and may provide a more meaningful basis for comparison of the CO
2
response between individuals.
An Evaluation of Stroke Intensive Care: Results in a Municipal Hospital
Authors: PITNER SAMUEL E. , MANCE CORNELIUS J.
Published: June 2011

One hundred consecutive cases with an admitting diagnosis of cerebrovascular disease treated in a four-bed Stroke Intensive Care Unit were reviewed in regard to final diagnosis and outcome. Eleven had final diagnoses other than cerebrovascular disease. Eighty-one had specific diagnoses as to major type of cerebrovascular disease present. The outcome in these cases was compared with that of 81 control cases matched for diagnosis only and blindly selected from concurrent admissions to an adjacent neurological ward. No significant differences in overall mortality (33% versus 27%) or in mortality by diagnostic category were found. This was true even if deaths in the first 48 hours were omitted from both groups to compensate for the selective admission of more seriously ill patients to the Stroke Intensive Care Unit. These results are compared to those reported by others. We concluded that specialized stroke intensive care units modeled on coronary care units do not have a significant impact on acute stroke mortality.
Localized Neurogenic Vasoconstriction of the Basilar Artery
Authors: BEVAN JOHN A. , BEVAN ROSEMARY D.
Published: June 2011

Ring segments from the caudal end of the basilar artery of the rabbit contract to electrical stimulation of their intramural nerve supply more than those from adjacent parts of the vertebral and the rostral three-fourths of the basilar arteries. The magnitude of developed neurogenic tension is approximately one-fourth that of the ear artery, a highly reactive muscular artery. The position of this reactive arterial segment suggests its role in the regulation of cerebral blood flow.
Cerebral Atherosclerosis in Japanese. 3. Predilection Site of Atherosclerotic Lesions
Authors: KIKUCHI Y. , YAMAMOTO H. , NAKAMURA M.
Published: June 2011

Four hundred twenty-three intracranial cerebral arteries (males and females) were obtained from the medicolegal autopsy cases. Special attention was given to the three sites and the circumferential distribution of lesions in order to investigate the effects of hydrodynamics on the development of cerebral atherosclerosis. The severest lesions were primarily found at the inner curvature at the terminal portion of the internal carotid artery, the medial portion at the origin of the anterior cerebral artery, and the posterior portion at the origin of the posterior cerebral artery. The present results obviously demonstrated the relationship between the predilection sites of atherosclerotic lesions and the shape of the cerebral arterial tree.