bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebral vasodilation during hypercapnia. Role of glibenclamide-sensitive potassium channels and nitric oxide.
Authors: Faraci F M , Breese K R , Heistad D D
Published: June 2011

The purpose of these experiments was to examine mechanisms by which hypercapnia produces vasodilatation in brain. We examined the hypothesis that dilatation of cerebral arterioles during hypercapnia is dependent on activation of ATP-sensitive potassium channels and formation of nitric oxide.

Diameters of cerebral arterioles were measured using a closed cranial window in anesthetized rabbits. Changes in diameter of arterioles were measured in response to topical application of acetylcholine and sodium nitroprusside and during two levels of systemic hypercapnia.

Increasing arterial PCO2 from 32 +/- 1 mm Hg (mean +/- SE) to 54 +/- 1 and 66 +/- 1 mm Hg dilated cerebral arterioles by 25 +/- 3% and 38 +/- 5%, respectively, from a control diameter of 93 +/- 3 microns. The response to the low level of hypercapnia was attenuated (25 +/- 3% versus 16 +/- 4%, P < .05) by glibenclamide (1 mumol/L), an inhibitor of ATP-sensitive potassium channels. Vasodilatation in response to the high level of hypercapnia was not affected by glibenclamide. Increases in arteriolar diameter in response to sodium nitroprusside were not inhibited by glibenclamide. NG-nitro-L-arginine (300 mumol/L), an inhibitor of nitric oxide synthase, completely inhibited dilatation of cerebral arterioles in response to the low level of hypercapnia and inhibited vasodilatation during the high level of hypercapnia by 66%.

Thus, activation of glibenclamide-sensitive potassium channels may contribute to dilatation of cerebral arterioles during hypercapnia. Cerebral vasodilatation during hypercapnia is dependent in large part on production of nitric oxide.
Primary medullary hemorrhage. Report of four cases and review of the literature.
Authors: Barinagarrementeria F , Cantú C
Published: June 2011

Primary medullary hemorrhage is uncommon. Its clinical profile and prognosis are not well known. We report four cases of medullary hemorrhage and a review of the English and French literature since 1964 to analyze the clinical presentation and prognosis.

Of sixteen case reports of medullary hemorrhage reviewed from the literature, sixteen contained sufficient information for review and are included in this report. The age distribution of the patients was between 13 and 72 years, and 10 of these patients were men. The most frequent symptoms at onset were vertigo, sensory symptoms, and dysphagia. Presenting signs included palatal weakness, nystagmus, hypoglossal palsy, cerebellar ataxia, and limb weakness. The diagnosis was made at autopsy in 3 patients, at surgery in 3, by computed tomography in 4, and more recently by magnetic resonance imaging in 6. In nine instances the etiology of hemorrhage was undetermined; a ruptured vascular malformation was the cause in 3 patients, 1 was attributed to the use of anticoagulants, and hypertension was the suspected cause in the other 3 patients. Mortality rate was 19%; however, survivors generally had nonincapacitating sequelaes.

These findings indicate that primary medullary hemorrhage presents with a characteristic syndrome of sudden onset of headache and vertigo with neurological signs that correspond to various combinations of medial and lateral medullary involvement. In those patients who survive, prognosis usually is good.
Effects of total hemoglobin and hemoglobin S concentration on cerebral blood flow during transfusion therapy to prevent stroke in sickle cell disease.
Authors: Hurlet-Jensen A M , Prohovnik I , Pavlakis S G , Piomelli S
Published: June 2011

The standard treatment of stroke in sickle cell disease is chronic transfusion to maintain the fraction of abnormal hemoglobin (hemoglobin S [HbS]) below 20%. Risks associated with such transfusion can be reduced by allowing higher HbS levels, but the physiological consequences of this modification are unknown. Cerebral blood flow is elevated in sickle cell disease proportionate to the degree of anemia and is reduced by transfusion. We tested the effects of various HbS levels on cerebral blood flow during the course of transfusion therapy.

We monitored cerebral blood flow (by the 133Xe inhalation method) in three patients whose chronic transfusion program was changed from a traditional regimen (HbS < 20%) to a moderate one, allowing HbS to rise to 45% to 50% between treatments. As expected, cerebral blood flow was higher with lower hemoglobin and higher HbS concentration. However, the HbS fraction appeared to exert a separate influence on the hyperemia, independent of total hemoglobin concentration. Furthermore, cerebral blood flow was higher during the modified regimen, despite equivalent anemia.

These results suggest caution in adapting the modified transfusion regimen. Although HbS concentrations of 50% did not cause any frank neurological sequelae, the possible consequences of the associated hyperemia over time are unknown. We conclude that larger clinical and physiological studies of moderate transfusion regimens (allowing higher concentration of HbS) are necessary before it can become standard therapy.
Patient preferences for stroke outcomes.
Authors: Solomon N A , Glick H A , Russo C J , Lee J , Schulman K A
Published: June 2011

In clinical trials stroke is reported as a major morbid outcome, but the impact of stroke on patients is not directly assessed. This study examines patient preferences for different outcomes of stroke, including death.

We presented patients with written case scenarios of stroke outcomes. The scenarios represented four categories of stroke severity (mild, moderate, severe, and fatal), and for nonfatal strokes the scenarios described motor, language, and cognitive deficits. Patients reported values for each of the 10 stroke scenarios using a rank-and-scale method over a 100-point range, with 100 representing perfect health and 0 corresponding to the worst possible health state.

One hundred seventeen of 209 consecutive patients at risk for stroke participated in this study. Severe strokes were uniformly rated as having low preference weights (mean +/- SD [median]: 3 +/- 4 [1] for disabling hemiplegia, 8 +/- 9 [5] for confusion, and 15 +/- 14 [10] for global aphasia), and severe motor impairment (a disabling hemiplegia) was rated as significantly worse than death. Even mild deficits resulted in substantial loss to patients (54 +/- 21 [55] for dysarthria and 53 +/- 21 [50] for mild anomia).

Strokes may result in a wide variety of post-stroke consequences for patients. Severe strokes may be viewed by patients as tantamount to or worse than death. Even mild strokes may cause significant declines in patient preferences for health states. These data are useful in interpreting studies that report stroke and death, in designing new studies that measure stroke in at-risk populations, and in helping patients reach treatment decisions about therapies designed to prevent strokes.
Cerebral autoregulation in orthostatic hypotension. A transcranial Doppler study.
Authors: Lagi A , Bacalli S , Cencetti S , Paggetti C , Colzi L
Published: June 2011

Transcranial Doppler measurements of blood flow velocity permit an assessment of variations in intracranial hemodynamics in response to acute arterial pressure variations. The purpose of this study was to scan healthy volunteers and patients with autonomic failure for differences in cerebral hemodynamic patterns under an acute hypotensive stimulus.

We used transcranial Doppler monitoring of blood flow velocity in the middle cerebral artery and noninvasive monitoring of arterial blood pressure and heart rate before, during, and after acute arterial hypotension induced by reactive hyperemia of the lower limbs.

After maximum hypotension, the mean blood flow velocity was higher in the healthy volunteers than in the patients. In the healthy subjects mean velocity rose significantly (P < .01) higher than arterial blood pressure after 30 seconds and 60 seconds; in the patients mean velocity and arterial pressure moved in parallel fashion. The diastolic blood flow velocity increased more in the control group than in the patients during the early stages of the test; furthermore, only in the healthy volunteers did it increase significantly more than arterial pressure after 30 seconds and 60 seconds. Regarding the pulsatility index, the differences between the two groups were similar to the diastolic velocity results.

(1) Monitoring of mean blood flow velocity showed the ability to maintain an adequate cerebral blood flow in healthy subjects; this mechanism was not efficient in the patients with autonomic failure. (2) Diastolic velocity and pulsatility index values clearly showed that only in healthy subjects were cerebral hemodynamics relatively independent of pressure values.
The layered fabric of cerebral artery fenestrations.
Authors: Finlay H M , Canham P B
Published: June 2011

Intravascular bridges, resulting from developmental anomalies of brain arteries, are now better known as arterial fenestrations. Their tendency to develop aneurysms, similar to arterial bifurcations, makes their anatomy and microstructure important for study.

Six segments of artery, each including a fenestration (five from the vertebrobasilar junction and one from the middle cerebral artery), were pressure distended, fixed, and sectioned. We made three-dimensional orientation measurements of smooth muscle and collagen, stained to enhance their birefringence, using the polarized light microscope.

The general contour of the fenestrations is streamlined with a thickened layered subendothelium at the trailing or distal edge, structurally similar to the region of convergence of major brain arteries. Defects of the medial layer were found at both proximal and distal edges of all the fenestrations. Results included regional mean orientations of individual layers, with circular SDs. The medial layer was found to be coherently aligned perpendicular to the direction of blood flow, with a mean circular SD of 12 degrees. The adventitia was less coherent (mean circular SD, 16 degrees) with the same average orientation, and the multilayered subendothelium had layers of obliquely oriented fibers with a wide range of coherence for individual fiber groups. Layers of the side regions were analogous to those in segments of brain artery and differed significantly from the proximal and distal edges of the fenestration structure.

The plasticity of form of the fenestrations at both the proximal and distal edges is in response to hemodynamic forces and is analogous to branching regions of brain arteries. Medial defects, a common feature in both brain arteries and fenestrations, may predispose the arterial fenestration to aneurysm formation.
Magnetic Resonance Imaging of Regional Cerebral Blood Oxygenation Changes Under Acetazolamide in Carotid Occlusive Disease
Authors: Kleinschmidt Andreas , Steinmetz Helmuth , Sitzer Matthias , Merboldt Klaus-Dietmar , Frahm Jens
Published: June 2011

Background
Gradient-echo magnetic resonance imaging can demonstrate changes in cerebral blood oxygenation with high spatiotemporal resolution. We have previously shown that this technique allows monitoring of autoregulatory responses under vasodilatory stress in the healthy human brain. Here the approach has been extended to assess impairment of the autoregulatory reserve capacity in patients with carotid occlusive disease.

Summary of Report
We studied four patients with unilateral occlusion of the internal carotid artery on a 2.0-T clinical high-field magnetic resonance system. Oxygenation-sensitive imaging was based on long-echo-time, gradient-echo sequences (repetition time, 62.5 milliseconds; echo time, 30 milliseconds) with low flip angles (10°) to emphasize changes in blood oxygenation rather than flow velocity. Dynamic recording monitored signal intensities before and after injecting 1 g of acetazolamide. In sections covering the hand area of the primary sensorimotor cortex, acetazolamide-induced magnetic resonance signal increases were attenuated in the vascular territories of occluded arteries. Lateralization of responses in the left and right hemispheric parts of the section corresponded to decreased hemodynamic reserve capacity as measured globally by transcranial Doppler ultrasonography.

Conclusions
The present findings indicate that magnetic resonance imaging can demonstrate exhaustion of the autoregulatory reserve capacity when monitoring cerebral blood oxygenation changes during vasodilatory stress. We suggest that this method can help to evaluate regional cerebral hemodynamics in patients with carotid occlusive disease.
Postpartum Cerebral Angiopathy Possibly Due to Bromocriptine Therapy
Authors: Janssens E. , Hommel M. , Mounier-Vehier F. , Leclerc X. , du Masgenet B. Guerin , Leys D.
Published: June 2011

Background
Eight cases of benign angiopathy of the postpartum period have been reported previously, none of which involved the administration of bromocriptine.

Case Description
We describe a case of benign cerebral angiopathy in a 20-year-old woman in the postpartum period occurring after bromocriptine therapy prescribed to suppress lactation.

Conclusions
Other adverse effects due to vasoconstriction have been reported during bromocriptine therapy, such as myocardial infarction and arterial hypertension. This case suggests that a similar mechanism may be possible in cerebral arteries, although the cause of vasoconstriction remains uncertain.
Determination of Cognitive Hemispheric Dominance by “Stereo” Transcranial Doppler Sonography
Authors: Rihs F. , Gutbrod K. , Gutbrod B. , Steiger H.-J. , Sturzenegger M. , Mattle H. P.
Published: June 2011

Background and Purpose
Transcranial Doppler sonography (TCD) can assess blood flow velocity changes induced by focal brain activation. Therefore, TCD may have the potential to identify hemispheric dominance for cognitive tasks.

Methods
Using a system with two TCD probes (“stereo” TCD), we monitored simultaneously both middle cerebral arteries (MCAs) of 14 healthy right-handed volunteers while they performed cognitive tasks. The averaged blood flow velocity ratio of the two MCAs and the hemispheric blood flow velocity shift induced by the cognitive task were calculated.

Results
In every subject, language tasks resulted in blood flow velocity shift to the left compared with visuospatial tasks. Mean MCA blood flow velocity shift to the left was 1.67%, 2.01%, and 2.31% in three language tasks. Mean blood flow velocity shift to the right was 1.67% and 2.31% in two visuospatial tasks.

Conclusions
Bilateral simultaneous MCA blood flow velocity monitoring and averaging during cognitive tasks can help to identify hemispheric dominance for cognitive tasks in individuals.
Changes in the Sex Ratio of Stroke Mortality in the Period of 1955 Through 1990
Authors: Zhang Xin Hua , Sasaki Satoshi , Kesteloot Hugo
Published: June 2011

Background and Purpose
Stroke mortality worldwide has decreased in men and women in most industrialized countries, except in eastern European countries. The purpose of this study was to compare the sex ratio of stroke mortality between populations and over time. This approach may help to determine the factors influencing this ratio.

Methods
The sex ratios (men to women) of stroke mortality between ages 55 to 64, 65 to 74, and 75 to 84 years from 27 populations between 1955 and the latest available year were analyzed using World Health Organization data. The relationship between log stroke mortality and age and the relationships between alcohol, animal fat, cigarette consumption, and urinary cation excretion and the sex ratio of stroke mortality were also analyzed.

Results
The mean sex ratio of stroke mortality increased 50%, 34%, and 15% in the three age classes, respectively, over 35 years. Highly significant relationships of log stroke mortality with age exist, which vary between men and women and among countries. In general, stroke mortality changed in the same direction in both sexes but decreased earlier and more rapidly in women than in men. Alcohol consumption and urinary sodium excretion correlated positively and significantly with the sex ratio. The time trends of the sex ratio also correlated positively and significantly with the time trends of cigarette consumption. No relationship with animal fat consumption was found.

Conclusions
The sex ratio of stroke mortality is increasing with time and decreasing with age. Differences in lifestyle among countries and over the last three decades may contribute partially to these differences in sex ratio.
Alteration of Intracellular Metabolite Diffusion in Rat Brain In Vivo During Ischemia and Reperfusion
Authors: Wick Markus , Nagatomo Yasushi , Prielmeier Franz , Frahm Jens
Published: June 2011

Background and Purpose
Diffusion-weighted MRI can demonstrate decreases of the apparent diffusion coefficient (ADC) of brain tissue water shortly after the onset of ischemia. To further elucidate underlying mechanisms, this study extended diffusion assessment to intracellular metabolites in rat brain in vivo before, during, and after ischemia.

Methods
Changes in molecular mobility were studied in a rat model of global forebrain ischemia (n=8, 20-minute occlusion, 120-minute reperfusion) with the use of diffusion-weighted localized proton MR spectroscopy. During ischemia and early reperfusion the time course of ADC changes was monitored by strongly diffusion-weighted spectra. ADC values of
N
-acetylaspartate, creatines, cholines, and
myo
-inositol were evaluated from series of differently diffusion-weighted spectra before ischemia, 90 minutes after reperfusion, and 60 minutes postmortem.

Results
Parallel to a rise in diffusion-weighted water signal (133±20%), pertinent intensities of all brain metabolites increased during ischemia. Changes were most pronounced for
myo
-inositol (46±9%) and smallest for
N
-acetylaspartate (12±4%). During reperfusion water ADC values returned to basal values, whereas metabolite ADC values were decreased by 22% (after 40 minutes). Postmortem ADC values (after 60 minutes) were reduced by 46% for water and 38% for metabolites.

Conclusions
The present findings indicate that water ADC changes during ischemic stroke are accompanied by significant alterations in intracellular mobility in both neuronal and glial cell populations as reflected by
N
-acetylaspartate and
myo
-inositol, respectively. Altered metabolite ADC values during reperfusion are consistent with irreversible tissue damage in this model and offer new means to assess circulatory and metabolic compromise.
Sensory Changes in the Ipsilateral Extremity
Authors: Kim Jong S. , Lee Jay H. , Lee Myoung C.
Published: June 2011

Background
Classically, patients with unilateral lateral medullary infarction exhibit sensory abnormalities over the ipsilateral face and contralateral hemibody. As a variant, bilateral or contralateral facial sensory changes can be seen. However, sensory changes in the ipsilateral extremities are extremely rare.

Case Descriptions
We describe three patients with lateral medullary syndrome in whom impaired deep sensation in the ipsilateral limbs was found. MRI results showed that the infarcts were located superficially in the lateral (case 1) and dorsal (cases 2 and 3) areas of the lower medulla, which probably involved the ascending or crossing dorsal column sensory tracts.

Conclusions
Although rare, impaired ipsilateral deep sensation is encountered in patients with lateral medullary infarction syndrome.
Fever in Acute Stroke Worsens Prognosis
Authors: Azzimondi Giuseppe , Bassein Leona , Nonino Francesco , Fiorani Laila , Vignatelli Luca , Re Giuseppe , D’Alessandro Roberto
Published: June 2011

Background and Purpose
No definitive data are yet available on the effects of body temperature on neurological damage after cerebral ischemia in humans. Experimental animal models have provided much evidence, but to our knowledge, only two studies on the relationship between fever and prognosis of stroke in humans have been published. The aim of our study was to investigate the prognostic role of fever in the first 7 days of hospitalization in a cohort of patients admitted to our hospital for acute stroke.

Methods
We analyzed the data of 183 patients included in a prospective observational prognostic study. Vital status at 30 days was considered the main outcome and was obtained for all patients. Age, level of consciousness, and glycemia at the time of hospitalization were considered covariates for an exact logistic regression analysis. The maximum temperature recorded during the first 7 days dichotomized as “no or low fever” versus “high fever” was added to the model. Death within 10 days, taken as a secondary outcome suggestive of death from neurological causes, was analyzed with exact permutation tests.

Results
Of the 183 patients analyzed in this study, 43% had fever during the first 7 days after hospitalization. The mean value of the maximum temperature recorded during the first 7 days in the 78 febrile patients was 38.3°C, and the median was 37.9°C. Onset of fever occurred in only 15% of febrile patients during the first day and in 49% on the second. The prognostic roles of age, level of consciousness, and glycemia were confirmed by exact logistic regression. Degree of consciousness impairment was the strongest prognostic variable, with an odds ratio (OR) of 11.4 (95% confidence interval [CI], 4.4 to 31.6). High fever (maximum temperature recorded during the first 7 days ≥37.9°C) was an independent factor for a worse prognosis, with an OR of 3.4 (95% CI, 1.2 to 9.5). The OR of dying within 10 days versus dying between 11 and 30 days was 4.9 (95% CI, 1.2 to 25.2) in patients with high fever with respect to all other patients.

Conclusions
Fever in the first 7 days was an independent predictor of poor outcome during the first month after a stroke. No data were available on the underlying causes of fever, but the higher risk of death in the first 10 days, most frequently attributed to neurological mechanisms, suggested that high temperature was an independent component of poor prognosis and not only an epiphenomenon of other complications in the course after a stroke. In agreement with animal studies, we found that patients with higher temperature had a worse stroke outcome.
Delay in Neurological Attention and Stroke Outcome
Authors: Dávalos Antoni , Castillo José , Martinez-Vila Eduardo
Published: June 2011

Background and Purpose
Despite efforts to reduce the delay between stroke onset and new interventional treatments, no studies have analyzed the repercussions of early neurological attention on the clinical outcome of stroke patients.

Methods
Data were obtained from 721 patients admitted consecutively for a transient ischemic attack or stroke to the neurology departments of 18 Spanish hospitals that followed the same diagnostic and therapeutic guidelines in the acute phase. Factors assessed were age, sex, Canadian Stroke Scale score on admission, previous Barthel Index, and delay before attention by the first physician, by emergency services, by a neurologist, and before hospitalization. Patients’ outcomes were classified as good (Barthel Index >60) or poor (Barthel Index ≤60 or in-hospital death) depending on patients’ functional capacity on discharge. The individual contribution of each of these variables on clinical outcome was estimated with logistic regression analysis.

Results
Patients in worse neurological condition on admission presented earlier to the first physician, emergency department, and neurologist. The mortality rate was not significantly modified by early or late presentation at the different medical stages. Logistic regression analysis revealed that the relative risk of poor outcome in patients seen by the neurologist after the first 6 hours from symptom onset was 5.6 (95% confidence interval, 3.4 to 9.2) (
P
<.0001). Multiple linear regression analysis showed that the delay before the patient received neurological attention correlated positively with the duration of hospitalization (
P
<.0001). The delays before the patient was seen by the first physician or the emergency department and before hospitalization were not independently related to clinical outcome or length of hospitalization.

Conclusions
Early neurological attention in acute stroke is related to better functional outcome and shorter hospitalization.
Immunohistochemical Detection of Ki-67 in Replicative Smooth Muscle Cells of Rabbit Carotid Arteries After Balloon Denudation
Authors: Aoyagi Masaru , Yamamoto Mari , Wakimoto Hiroaki , Azuma Hiroshi , Hirakawa Kimiyoshi , Yamamoto Kiyotaka
Published: June 2011

Background and Purpose
Ki-67 immunohistochemistry has been shown to be useful for paraffin sections from human species after wet heating. We applied Ki-67 immunohistochemistry to rabbit arteries after balloon denudation and compared the results with proliferating cell nuclear antigen (PCNA) immunohistochemistry.

Methods
Monoclonal antibodies MIB-1 for Ki-67 and PC-10 for PCNA were used to detect replicative smooth muscle cells in rabbit carotid arteries during a period of 4 weeks after balloon endothelial denudation.

Results
We demonstrated clear immunoreactivities for Ki-67 in paraffin sections of rabbit arteries after hydrated autoclaving. Ki-67–positive smooth muscle cells appeared throughout the thickened intima 1 week after endothelial denudation. At 2 weeks, Ki-67–positive cells were confined to the surface layer of the intima. PCNA-postive cells appeared in almost the same location by 2 weeks after endothelial denudation but were significantly greater in number than Ki-67–positive cells. PCNA-positive cells remained in the surface layer of the intima 4 weeks after endothelial denudation, while Ki-67–positive cells had almost disappeared from the intima.

Conclusions
Our results indicate that Ki-67 immunohistochemistry using MIB-1 monoclonal antibody provides a powerful tool, even in rabbit species, for the detection of replicative smooth muscle cells during the repair of arterial injury and that it detects replicative cells more accurately than PCNA immunohistochemistry.
Epidemiology of Stroke in Kaunas, Lithuania
Authors: Rastenyte Daiva , Cepaitis Zygimantas , Sarti Cinzia , Bluzhas Juozas , Tuomilehto Jaakko
Published: June 2011

Background and Purpose
In Lithuania, only routine mortality statistics have thus far provided data on the epidemiology of stroke. This study aims to assess the mortality, incidence, and case-fatality rate of stroke in the city of Kaunas, Lithuania, during 1986 to 1988.

Methods
A community-based stroke register was set up in 1986 to collect data on all suspected events of acute stroke that occurred in the population aged 35 to 64 years permanently residing in Kaunas. Crude and age-standardized attack rates, incidence, mortality, and case-fatality rates were calculated for the period studied.

Results
Among men, the average age-standardized incidence of stroke (referring to first-ever events) was 230/100 000, the attack rate (all events) was 300/100 000, and the mortality from all strokes was 68/100 000. Among women, the corresponding rates were 131/100 000, 154/100 000, and 35/100 000, respectively. Of 973 acute stroke events registered, 80% were first-ever strokes. The age-adjusted 28-day overall case-fatality rate and the case-fatality rate of first-ever stroke were 23.3% and 19.8% in men and 21.8% and 21.3% in women, respectively.

Conclusions
The findings from this first assessment of the incidence and mortality of stroke show that in the mid-1980s both were high in Kaunas compared with other countries. The case-fatality rate was similar to that reported for most other European countries. Further investigations are being carried out to assess the trends in mortality, incidence, and risk factors of stroke in the Kaunas population.
N
-Acetylcysteine Enhances Hippocampal Neuronal Survival After Transient Forebrain Ischemia in Rats
Authors: Knuckey Neville W. , Palm Donald , Primiano Michael , Epstein Mel H. , Johanson Conrad E.
Published: June 2011

Background and Purpose
Free radical scavengers enhance neuronal survival in some models of transient forebrain ischemia. Recent experiments have suggested that
N
-acetylcysteine prevents cellular injury after a reperfusion injury. No information is available regarding the neuroprotective potential of the free radical scavenger
N
-acetylcysteine after transient forebrain ischemia. In this study we evaluated the potential of
N
-acetylcysteine to improve hippocampal neuronal survival after transient forebrain ischemia in the rat.

Methods
In series A and B, ventilated, paralyzed, normothermic rats had 10 minutes of transient forebrain ischemia induced by bilateral carotid occlusion with hypotension induced by blood withdrawal (mean arterial blood pressure, 45 mm Hg). In series A, animals were administered
N
-acetylcysteine (163 mg/kg) 30 minutes and 5 minutes before transient forebrain ischemia. In series B,
N
-acetylcysteine (326 mg/kg) was administered 15 minutes after transient forebrain ischemia. In series C,
N
-acetylcysteine (326 mg/kg) was administered 15 minutes after transient forebrain ischemia in animals with a mean arterial blood pressure of 30 mm Hg during transient forebrain ischemia. All series had normal control, sham, and vehicle treatment groups. In all series, the rats were allowed to recover and were killed at 7 days after ischemia. The effect of forebrain ischemia was assessed by evaluating the number of viable neurons at bregma sections −3.3, −3.8, and −4.3 of the CA1 region of the hippocampus.

Results
The results demonstrated no physiological difference among the various treatment groups. There were no differences in the number of viable neurons between the transient forebrain ischemia with no treatment group and the vehicle (saline)-treated transient forebrain ischemic groups. Animals pretreated with
N
-acetylcysteine (mean number of neurons, 84±6) had a significant increase (
P
<.05) in neuronal survival compared with vehicle-treated animals (mean number of neurons, 43±4). Animals posttreated with
N
-acetylcysteine (mean number of neurons, 89±9) had a significant increase in neuronal survival compared with vehicle-treated animals (mean number of neurons, 7±1). However,
N
-acetylcysteine protection was only partial at 45 mm Hg and did not improve neuronal survival (mean number of neurons, 22±3) in animals with a more severe ischemic insult (mean arterial blood pressure, 30 mm Hg during transient forebrain ischemia) compared with vehicle-treated animals (mean number of neurons, 10±1).

Conclusions
N
-Acetylcysteine partially improved neuronal survival when administered before or after ischemia following transient cerebral ischemia (mean arterial blood pressure, 45 mm Hg) but not with a more severe ischemic insult of 10 minutes of transient cerebral ischemia with a mean arterial blood pressure of 30 mm Hg.
Embolic Stroke Following Thrombolytic Therapy for Myocardial Infarction in a Patient With Preexisting Ventricular Thrombi
Authors: Bautista Ramon Edmundo D.
Published: June 2011

Background
Dislodging of preexisting cardiac thrombi has been a reported but unconfirmed cause of embolic strokes after thrombolytic therapy for myocardial infarction.

Case Description
An 82-year-old woman was admitted with congestive heart failure. Initial echocardiogram demonstrated ventricular thrombi. Three days later she experienced an inferior wall myocardial infarction, and intravenous streptokinase was administered. Six hours later she abruptly developed a global aphasia with a dense right hemiparesis. Repeat echocardiogram did not show any thrombus.

Conclusions
Thrombolytic therapy may have caused embolization of ventricular thrombi. Cardiac conditions that predispose to embolic strokes are not established contraindications to thrombolytic therapy. The potential for thrombolytic therapy to produce embolization in patients with preexisting cardiac mural thrombi should be evaluated.
Quality of Life After Stroke
Authors: de Haan R.J. , Limburg M. , Van der Meulen J.H.P. , Jacobs H.M. , Aaronson N.K.
Published: June 2011

Background and Purpose
Little attention has been focused on the relationship between neurological lesions and quality of life (QL) in stroke research. The purpose of this study was to analyze the impact of stroke types and lesion locations on QL.

Methods
The study sample was composed of 441 stroke patients. Lesion locations and stroke types were divided into 194 left-sided and 173 right-sided lesions, 61 infratentorial strokes (55 infarctions and 6 hemorrhages), and 335 supratentorial strokes (204 [sub]cortical infarctions, 82 lacunar infarctions, and 49 hemorrhages). Six months after stroke, QL was assessed with the Sickness Impact Profile. Age-adjusted QL scores were expressed in standard scores.

Results
Although patients with left-sided lesions had more speech pathology (
P
<.001), there was slightly more QL deterioration in patients with right-sided lesions. Patients with infratentorial strokes reported better overall functioning than patients with supratentorial strokes (
P
=.02). Patients with lacunar infarction had less dysfunction compared to patients with (sub)cortical lesions (
P
<.001). There was no difference in QL between supratentorial (sub)cortical infarcts and hemorrhages. Lesion locations and stroke types did not affect patients’ emotional distress. Severely impaired QL patterns were related significantly to older age (
P
<.001), comorbidity (
P
=.02), stroke severity (
P
<.001), and supratentorial lesions (
P
=.02).

Conclusions
There is only a weak relationship between lesion laterality and QL. Survivors of hemorrhagic strokes do not evidence more QL impairment than survivors of ischemic strokes. Stroke per se is not unequivocally followed by emotional discomfort. In addition to stroke type, patient and clinical characteristics are also important in explaining impaired QL patterns.
Stroke Patterns in Unilateral Atherothrombotic Occlusion of the Internal Carotid Artery
Authors: Mounier-Vehier F. , Leys D. , Pruvo J. P.
Published: June 2011

Background and Purpose
Stroke patterns in patients with occlusion of the internal carotid artery (ICA) and no potential cardiac cause of stroke remain unknown. The aim of our study was to determine the pattern of stroke in patients with an occlusion of the ICA of presumed atherosclerotic origin.

Methods
Of 873 consecutive patients admitted for an acute ischemic event during a 49-month period, 40 (29 men and 11 women; mean age, 63 years) had a unilateral occlusion of the ICA of presumed atherosclerotic origin and no other potential cause of stroke. They underwent two computed tomographic scans, Doppler ultrasonography, and B-mode echotomography of the cervical arteries or angiography and echocardiography. We compared stroke patterns between both hemispheres.

Results
We found ipsilateral infarcts in 32 patients (80%; 99% confidence interval [CI], 64% to 96%) and contralateral infarcts in 12 patients (30%; 99% CI, 11% to 49%). Infarcts ipsilateral to the ICA occlusion were more likely to be cortical (odds ratio, 9.33; 99% CI, 2.4 to 36.35) or subcortical infarcts 15 mm or greater (odds ratio, 16.71; 99% CI, 1.05 to 267.3). The prevalence of subcortical infarcts less than 15 mm did not differ between hemispheres.

Conclusions
Symptomatic infarcts related to an ICA occlusion are more likely to be cortical or large subcortical infarcts. Small subcortical infarcts have the same prevalence in both hemispheres and therefore may be coincidental.
Early Prediction of Stroke Severity
Authors: Chamorro A. , Vila N. , Ascaso C. , Saiz A. , Montalvo J. , Alonso P. , Tolosa E.
Published: June 2011

Background and Purpose
Early predictors of functional outcome after stroke are necessary for better planning of treatment and care.

Methods
We evaluated prospectively early clinical predictors of short-term functional outcome in a group of patients with ischemic cerebral infarction and explored whether the intensity of the acute-phase response provided further information concerning the short-term functional outcome. We evaluated a group of 208 ischemic stroke patients using the Mathew scale at entry. All patients had neuroimaging studies and routine blood tests, including erythrocyte sedimentation rate (ESR), within 72 hours from clinical onset. At discharge, functional outcome was graded according to a Stroke Outcome Scale.

Results
Larger infarcts, more embolic infarcts, and fewer lacunar infarcts were observed in the poor-outcome group. Vascular risk factors, radiological findings not related to the index stroke, time to admission, and treatment were similar in the two outcome groups. Variables with statistically significant differences between outcome groups included the following: age >65 years, female sex, admission Mathew score <75, worsening at clinical presentation, infarct volume >6 cm
3
, complicating infections, fasting glucose >110 mg, nonfasting glucose >130 mg, and elevated ESR. With stepwise logistic regression analysis, Mathew score on admission, infarct volume, mode of clinical presentation, and ESR remained in the predictive model of stroke outcome, with a sensitivity and specificity of 89.91% and 85.71%, respectively. After removing the computed tomographic information from the model the same variables remained, with a sensitivity and specificity of 83.05% and 94.29%, respectively.

Conclusions
Infarct size and clinical severity on admission are the stronger predictors of short-term functional outcome. Mode of clinical presentation, clinical evolution during the first day of stroke, and ESR are also independent predictors of short-term stroke outcome. These findings might be indicative of an inadequate collateral profile and/or a more pronounced prothrombotic state.
Retinopathy as a Risk Factor for Nonembolic Stroke in Diabetic Subjects
Authors: Petitti Diana B. , Bhatt Hilarey
Published: June 2011

Background and Purpose
Age, hypertension, and the presence of diabetic nephropathy and coronary and peripheral vascular disease are established risk factors for stroke in diabetic subjects, but the association of retinopathy with stroke risk is less clear.

Methods
In this nested case-control study, we examined the association of retinopathy with risk of nonembolic ischemic stroke in diabetes. In a cohort of 2124 diabetic persons identified at multiphasic health checkups during the period from 1979 through 1985, 56 suffered a nonembolic ischemic stroke during follow-up, which extended through 1991. For each case subject, one diabetic control subject matched by sex and year of birth was selected from the same cohort of diabetics. Medical records were reviewed to gather information on risk factors for stroke. Information on risk factors was retrieved for 52 of the 56 cases.

Results
The estimated relative risk of stroke in diabetic subjects with retinopathy was 2.8 (95% confidence interval, 1.2 to 6.9). After adjustment for age, sex, smoking, use of insulin, average systolic blood pressure, and average random glucose, the estimated relative risk was 4.0 (95% confidence interval, 1.0 to 14.5). The relative risk of stroke in diabetic subjects with retinopathy remained elevated after exclusion of those with complications other than retinopathy.

Conclusions
Stroke prevention in diabetic persons is a challenge. Diabetic subjects with retinopathy appear to be a group at particularly high risk of ischemic stroke. Development of preventive interventions might focus on this group.
Effects of Picotamide, an Antithromboxane Agent, on Carotid Atherosclerotic Evolution
Authors: Cocozza Manlio , Picano Tommaso , Oliviero Ugo , Russo Nicola , Coto Vincenzo , Milani Massimo
Published: June 2011

Background and Purpose
We assessed the effects of long-term treatment with picotamide, an antiplatelet agent with dual antithromboxane activity, on the evolution of early asymptomatic carotid atherosclerotic lesions in diabetic patients.

Methods
In a double-blind, placebo-controlled, 2-year study, 50 type II normotensive diabetic patients (35 men; mean age, 66±5 years) with asymptomatic mild or moderate nonstenotic (<50%) carotid atherosclerotic lesions and negative history of cerebrovascular ischemic events were enrolled and randomly given picotamide (300 mg TID) or the corresponding placebo. A high-resolution, real-time B-scan echographic assessment of carotid arteries was performed at baseline and after 1, 3, 6, 12, 18, and 24 months of double-blind treatment. Prevalence and evolutionary trends of carotid atherosclerotic lesions (number per patient and mean stenosis expressed as percent) were considered as efficacy primary end points.

Results
At baseline, mean±SD numbers of carotid atherosclerotic lesions per patient were 2.7±1.8 and 2.2±1.2 in the picotamide and placebo groups, respectively. Mean±SD percent stenosis was 25.3±7% in the picotamide group and 27.3±6% in the placebo group. Forty-nine patients completed the study. At month 24, the placebo group (n=24) showed a significant progression in number of carotid atherosclerotic lesions (3.04±1.8;
P
<.02 versus baseline) and in mean percent stenosis (35±17%; 95% confidence interval, 33% to 37%;
P
<.01 versus baseline). In the picotamide group (n=25), mean number of carotid atherosclerotic lesions (2.7±1.6) and percent stenosis (26±9%; 95% confidence interval, 24.8% to 27.2%) remained unchanged. At month 24, compared with randomized placebo, lesion numbers (
P
<.03) and percent stenosis (
P
<.01) in the picotamide group were significantly lower. During the study, 12 patients experienced major or minor ischemic vascular events (9 in the placebo group and 3 in the picotamide group;
P
=.07).

Conclusions
In diabetic patients compared with patients receiving placebo, long-term treatment with picotamide can slow the evolution of early carotid atherosclerotic lesions, inhibiting progression of plaque number and growth.
Study of Aneurysmal Subarachnoid Hemorrhage in Izumo City, Japan
Authors: Inagawa Tetsuji , Tokuda Yoshio , Ohbayashi Naohiko , Takaya Mikio , Moritake Kouzo
Published: June 2011

Background and Purpose
Estimation of the actual incidence rate of subarachnoid hemorrhage and evaluation of the treatment require the inclusion of all patients in a defined geographic area.

Methods
During 1987 through 1992 in Izumo City, Japan, we estimated the incidence rate of subarachnoid hemorrhage by including dead-on-arrival patients and by further adding the results obtained after reviewing all death certificates registered in this city in the corresponding period. In addition, we compared the management and surgical outcomes in hospitalized patients from 1987 through 1992 with outcomes from 1980 through 1986.

Results
During 1987 through 1992, we diagnosed 123 patients as having subarachnoid hemorrhage. The crude and the age- and sex-adjusted incidence rates using the 1990 population statistics for Japan were 25 (95% confidence interval, 21 to 30) per 100 000/y and 23 (95% confidence interval, 19 to 28) per 100 000/y for all ages, respectively; these occurrences are the highest among those reported to date. Of these patients, 8% died before receiving medical attention, 27% in the first week, and 39% at 1 month. The survival curve for 2 years improved significantly from 1980-1986 to 1987-1992 in patients with admission grades 4 and 5 (
P
=.035) and in operated patients with preoperative grades 1 through 3 (
P
=.036). However, there was little improvement in the overall management results (
P
=.168), possibly because patients with high risk and/or old age were admitted and/or diagnosed more often in the latter period.

Conclusions
The incidence rate of subarachnoid hemorrhage is much higher than that reported so far in the literature, and despite improvement of management and surgical therapy, the actual case-fatality rate is still high, mainly because of the high mortality rate directly associated with the primary bleeding.
Alcohol Intake and the Risk of Cardiovascular Disease in Middle-Aged Japanese Men
Authors: Iso Hiroyasu , Kitamura Akihiko , Shimamoto Takashi , Sankai Tomoko , Naito Yoshihiko , Sato Shinichi , Kiyama Masahiko , Iida Minoru , Komachi Yoshio
Published: June 2011

Background and Purpose
Understanding the effects of alcohol intake on stroke and other cardiovascular diseases is an important issue for public health.

Methods
A 10.5-year prospective study of the relationship between alcohol intake and cardiovascular disease incidence was conducted in 2890 men, aged 40 to 69 years and free of a history of stroke and coronary heart disease, in three rural communities of Japan.

Results
One hundred seventy-eight strokes (40 intracerebral hemorrhages, 18 subarachnoid hemorrhages, 104 nonhemorrhagic strokes, and 16 unclassified strokes), 34 coronary heart disease events, and 19 sudden unclassified deaths occurred. Drinkers of ≥70 g/d ethanol had an approximately 2.5 times higher age-adjusted risk of all stroke than never-drinkers; the excess risk was more evident for hemorrhagic stroke than nonhemorrhagic stroke. When hypertension category, serum total cholesterol level, cigarette smoking, and diabetes mellitus were taken into account, these excess risks were reduced but remained significant for all stroke (2.0; 95% confidence interval, 1.3 to 3.1) and hemorrhagic stroke (3.4; 95% confidence interval, 1.2 to 9.2). A J-shaped relationship was suggested between alcohol intake and risk of nonhemorrhagic stroke; drinkers of <42 g/d ethanol had a slightly lower risk and heavy drinkers had a higher risk than never-drinkers. Current drinkers had a slightly lower risk of coronary heart disease than never-drinkers, although the risk difference was not statistically significant. The age-adjusted risk of sudden death was 10 times higher in heavy drinkers than never-drinkers, and the excess risk did not change when the covariates were controlled for. Total cardiovascular disease showed a similar pattern as did all stroke.

Conclusions
Heavy drinking appeared to increase the risk of hemorrhagic stroke, in part due to hypertension, and to increase the risk of sudden death, which was probably due to drinking per se. Light or moderate alcohol consumption seemed to protect against nonhemorrhagic stroke and coronary heart disease.
Predictors of Major Vascular Events in Patients With a Transient Ischemic Attack or Minor Ischemic Stroke and With Nonrheumatic Atrial Fibrillation
Authors: van Latum J.C. , Koudstaal P.J. , Venables G.S. , van Gijn J. , Kappelle L.J. , Algra A.
Published: June 2011

Background and Purpose
The risk of major vascular events after an initial episode of cerebral ischemia in patients with nonrheumatic atrial fibrillation (NRAF) varies from 2% to 15% in the first year and is approximately 5% yearly thereafter. Few studies have reported on risk factors that can be used to identify high-risk subgroups within this patient population.

Methods
We studied the predictive value of several easily obtainable clinical characteristics in a group of 375 placebo-treated patients with NRAF and a recent episode of transient or nondisabling cerebral ischemia who were entered in a multicenter clinical trial. The mean follow-up was 1.6 years.

Results
By means of multivariate modeling, six independent variables were identified: history of previous thromboembolism, ischemic heart disease, enlarged cardiothoracic ratio on chest roentgenogram, systolic blood pressure greater than 160 mm Hg at study entry, NRAF for more than 1 year, and presence of an ischemic lesion on CT scan. These variables could also be used to stratify patients in low-, medium-, and high-risk subgroups for the other two arms of the trial, those treated with anticoagulation and aspirin. Patients older than 75 years with three or more risk factors seemingly benefited less from both aspirin and anticoagulant treatment.

Conclusions
Easily obtainable patient characteristics are helpful in estimating the potential effect of adequate secondary prevention in patients with NRAF who recently suffered a transient ischemic attack or minor ischemic stroke.