bluuebunny/crossref_metadata_2025 huggingface dataset:
Emergency Medical Services-Based Community Stroke Education
Authors: Tadros Allison , Crocco Todd , Davis Stephen M. , Newman Jeremy , Mullen Jeffrey , Best Ronald , Teets Anthony , Maxwell Charles , Slaughter Barbara , Teter Stellman
Published: April 2009

Background and Purpose—

Although previous studies using mass media have demonstrated successful public stroke awareness campaigns, they may have been too costly for smaller communities to implement. The goal of this study was to investigate if a novel emergency medical services (EMS) -sponsored community awareness campaign could increase public stroke awareness.

Methods—

This was a pre- and postintervention study with 2 phases conducted between August 2005 and July 2007. During Phase I, strategic placement of stroke education media by EMS personnel was implemented in one county over a 2-year period. Five random-digit, standardized phone surveys measuring stroke awareness were conducted with county residents to assess the campaign’s impact. In Phase II, EMS interventions and random-digit measurements were conducted in 4 additional counties with 4 counties randomly selected as controls.

Results—

A pattern of increasing stroke knowledge after exposure to the EMS intervention followed by declines in the absence of the intervention was observed during Phase I. EMS interventions also demonstrated a positive effect on the stroke knowledge of residents who lived in counties exposed to the intervention during Phase II with a statistically significant (
P
<0.05) increase observed in the proportion of respondents that named 2 stroke risk factors and 3 symptoms in comparison to either no changes or declines in the control counties. No evidence of a positive impact on knowledge of calling 911 for stroke was observed.

Conclusion—

Results of this study suggest that the public’s knowledge of stroke signs and symptoms was increased using communitywide EMS-based programs. Additional studies are needed to determine optimal methods for educating the public regarding the need to call 911 for stroke and to confirm these results in other locales.
Degeneration of Astrocytic Processes and Their Mitochondria in Cerebral Cortical Regions Peripheral to the Cortical Infarction
Authors: Ito Umeo , Hakamata Yoji , Kawakami Emiko , Oyanagi Kiyomitsu
Published: April 2009

Background and Purpose—

Astrocytes support neuronal functions by regulating the extracellular ion-homeostasis and levels of neurotransmitters, and by providing fuel such as lactate to the neurons via their astrocytic processes (APs). Whether injured APs are associated with neuronal survival/death is still an unanswered question. We investigated APs in the neuropil, especially those around astrocytes and normal-appearing, degenerating, and dead neurons in cerebral cortical regions peripheral to the cortical infarction (RPI).

Methods—

Stroke-positive gerbils were euthanized at various times after the ischemic insult. Ultrathin sections were obtained from the RPI sectioned coronally at the infundibular level. We counted the number of normal-appearing, degenerated, and dead neurons and astrocytes in paraffin sections, the number of cut-ends and mitochondria in APs in the neuropil on electron-microscopic photographs, and determined the percent-volume of APs by Weibel point-counting method. We compared the number of cut-ends and mitochondria and percent-volume of APs around astrocytes at 5 hours and 48 hours, and around normal-appearing, degenerated, and dead neurons at 12 hours.

Results—

Although the number of astrocytes did not change (average of 12.3±0.20%) during 0 to 48 hours, that of the dead neurons increased from 9.71±1.34 to 44.39±1.40% during 5 to 48 hours postischemia. The number of normal-appearing APs and mitochondria in APs decreased respectively from 13.49±0.65 to 1.61±0.14/28.20 μm
2
and from 1.86±0.18 to 0.61±0.07/28.20 μm
2
in the neuropil during 0 to 48 hours. The number of normal-appearing APs around astrocytes decreased from 12.3±0.19 to 1.7±0.05/38.33 μm
2
with an increase in percent-volume of degenerated APs from 1.17±0.04 to 11.45±0.23%, from 5 to 48 hours postischemia. The number of normal-appearing APs decreased from 4.36±0.52 to1.56±0.17/38.33 μm
2
with an increase in percent-volume of degenerated APs, from 2.41±0.52 to 12.55±1.0%, from around the normal-appearing to dead neurons, at 12 hours.

Conclusions—

In the RPI, heterogeneous degeneration of APs was closely associated with disseminated selective neuronal necrosis and the maturation phenomenon seen in ischemic neuronal injury.
Relationship Between Hyperacute Blood Pressure and Outcome After Ischemic Stroke
Authors: Sare Gillian M. , Ali Myzoon , Shuaib Ashfaq , Bath Philip M.W.
Published: April 2009

Background and Purpose—

High blood pressure (BP) is associated independently with poor outcome after acute ischemic stroke, although in most analyses “baseline” BP was measured 24 hours or more postictus, and not during the hyperacute period.

Methods—

Analyses included 1722 patients in hyperacute trials (recruitment <8 hours) from the Virtual Stroke International Stroke Trial Archive (VISTA) Collaboration. Data on BP at enrolment and after 1, 2, 16, 24, 48, and 72 hours, neurological impairment at 7 days (NIHSS), and functional outcome at 90 days (modified Rankin scale) were assessed using logistic regression models, adjusted for confounding variables; results are for 10-mm Hg change in BP.

Results—

Mean time to enrolment was 3.7 hours (range 1.0 to 7.9). High systolic BP (SBP) was significantly associated with increased neurological impairment (odds ratio, OR 1.06, 95% confidence interval, 95% CI 1.01 to 1.12), and poor functional outcome; odds ratios for both increased with later BP measurements made at up to 24 hours poststroke. Smaller (versus larger) declines in SBP over the first 24 hours were significantly associated with poor NIHSS scores (OR 1.16, 95% CI 1.05 to 1.27) and functional outcome (OR 1.23, 95% CI 1.13 to 1.34). A large variability in SBP was also associated with poor functional outcome.

Conclusions—

High SBP and large variability in SBP in the hyperacute stages of ischemic stroke are associated with increased neurological impairment and poor functional outcome, as are small falls in SBP over the first 24 hours.
Effects of the End Point Adjudication Process on the Results of the Perindopril Protection Against Recurrent Stroke Study (PROGRESS)
Authors: Ninomiya Toshiharu , Donnan Geoff , Anderson Neil , Bladin Chris , Chambers Brian , Gordon Gary , Sharpe Norman , Chalmers John , Woodward Mark , Neal Bruce
Published: April 2009

Background and Purpose—

End point adjudication committees (EPAC) are widely used in large-scale clinical trials to ensure the robustness of diagnosis for end points.

Methods—

The Perindopril Protection Against Recurrent Stroke Study (PROGRESS) was a double-blind randomized trial of blood pressure lowering in 6105 participants with pre-existing cerebrovascular disease. Separate estimates of the effects of randomized treatment were determined using Cox regression models that were based on the unadjudicated events initially reported by the investigator and on the final events assigned by the EPAC.

Results—

There were 992 strokes initially reported by the investigators and 894 (90%) retained these diagnoses after adjudication by the EPAC. The hazard ratios (95% CIs) for the effect of randomized treatment on stroke were 0.74 (0.64 to 0.85) based on the investigator diagnoses and 0.72 (0.62 to 0.83) based on the EPAC diagnoses (
P
homogeneity=0.7). For each stroke subtype reported, the corresponding numbers of diagnoses (investigators/EPAC) were ischemic (593/565), hemorrhagic (124/111), and unknown (124/93) with no impact of the EPAC review on the estimates of treatment effects (all
P
homogeneity >0.3). There was likewise no detectable effect of reclassification of diagnoses for the effect estimates calculated for myocardial infarction or the main causes of death (all
P
homogeneity >0.5).

Conclusion—

The EPAC process had no discernible impact on the trial conclusions. Very large trials powered to detect effects on stroke subtypes might obtain real scientific gain from an EPAC, but in the case of PROGRESS, the value of the EPAC was in the reassurance it provided.
Hemorrhagic and Ischemic Strokes Compared
Authors: Andersen Klaus Kaae , Olsen Tom Skyhøj , Dehlendorff Christian , Kammersgaard Lars Peter
Published: April 2009

Background and Purpose—

Stroke patients with hemorrhagic (HS) and ischemic strokes were compared with regard to stroke severity, mortality, and cardiovascular risk factors.

Methods—

A registry started in 2001, with the aim of registering all hospitalized stroke patients in Denmark, now holds information for 39 484 patients. The patients underwent an evaluation including stroke severity (Scandinavian Stroke Scale), CT, and cardiovascular risk factors. They were followed-up from admission until death or censoring in 2007. Independent predictors of death were identified by means of a survival model based on 25 123 individuals with a complete data set.

Results—

Of the patients 3993 (10.1%) had HS. Stroke severity was almost linearly related to the probability of having HS (2% in patients with the mildest stroke and 30% in those with the most severe strokes). Factors favoring ischemic strokes vs HS were diabetes, atrial fibrillation, previous myocardial infarction, previous stroke, and intermittent arterial claudication. Smoking and alcohol consumption favored HS, whereas age, sex, and hypertension did not herald stroke type. Compared with ischemic strokes, HS was associated with an overall higher mortality risk (HR, 1.564; 95% CI, 1.441–1.696). The increased risk was, however, time-dependent; initially, risk was 4-fold, after 1 week it was 2.5-fold, and after 3 weeks it was 1.5-fold. After 3 months stroke type did not correlate to mortality.

Conclusion—

Strokes are generally more severe in patients with HS. Within the first 3 months after stroke, HS is associated with a considerable increase of mortality, which is specifically associated with the hemorrhagic nature of the lesion.
Evaluation of MR-Derived Cerebral Oxygen Metabolic Index in Experimental Hyperoxic Hypercapnia, Hypoxia, and Ischemia
Authors: An Hongyu , Liu Qingwei , Chen Yasheng , Lin Weili
Published: April 2009

Background and Purpose—

A noninvasive MRI method to measure cerebral oxygen metabolism has the potential to assess tissue viability during cerebral ischemia. The purposes of this study were to validate MR oxygenation measurements across a wide range of global cerebral oxygenation and to examine the spatiotemporal evolution of oxygen metabolism during focal middle cerebral artery occlusion in rats.

Methods—

A group of rats (n=28) under normal, hyperoxic hypercapnia and hypoxia were studied to compare MR-measured cerebral oxygen saturation (O
2
Sat
MRv
) with blood gas oximetry measurements in the jugular vein (O
2
Sat
JV
) and superior sagittal sinus (O
2
Sat
SSS
). In a separate group of rats (n=31), MR-measured cerebral oxygen metabolic index (MR_COMI) was acquired at multiple time points during middle cerebral artery occlusion. Histogram analysis was performed on the normalized MR_COMI (rMR_COMI) to examine evolution of oxygen metabolism during acute ischemia.

Results—

Highly linear relationships were obtained between O
2
Sat
MRv
and O
2
Sat
JV
/O
2
Sat
SSS
in rats under global cerebral oxygenation alterations. In the focal ischemia study, rMR_COMI values were significantly lower within the areas of eventual infarction than other regions. Moreover, the rMR_COMI values within the ischemic territory decreased with time, concomitant with an increase in the number of voxels with severely impaired oxygen metabolism.

Conclusion—

Accurate estimates of O
2
Sat
MRv
can be obtained across a broad and physiologically relevant range of cerebral oxygenation. Furthermore, this method demonstrates a dynamic alteration of cerebral oxygen metabolism during acute ischemia in rats.
MRI-Based Selection for Intra-Arterial Stroke Therapy
Authors: Yoo Albert J. , Verduzco Luis A. , Schaefer Pamela W. , Hirsch Joshua A. , Rabinov James D. , González R. Gilberto
Published: April 2009

Background and Purpose—

Recent studies demonstrate that an acute diffusion-weighted imaging lesion volume >70 cm
3
predicts poor outcome in patients with stroke. We sought to determine if this threshold could identify patients treated with intra-arterial therapy who would do poorly despite reperfusion. In patients with initial infarcts <70 cm
3
, we sought to determine what effect recanalization and time to recanalization had on infarct growth and functional outcome.

Methods—

We retrospectively studied 34 consecutive patients with anterior circulation stroke who underwent pretreatment diffusion-weighted imaging and perfusion-weighted imaging and subsequent intra-arterial therapy. Recanalization success and time to recanalization were recorded. Initial diffusion-weighted imaging and mean transit time lesion and final infarct volumes were determined. Patients were stratified based on initial infarct volume, recanalization status, and time to recanalization. Statistical tests were performed to assess differences in clinical and imaging outcomes. Good clinical outcome was defined as a 3-month modified Rankin Scale score ≤2.

Results—

Among patients with initial infarcts >70 cm
3
, all had poor outcomes despite a 50% recanalization rate with mean infarct growth of 114 cm
3
. These patients also had the largest mean transit time volumes (
P
<0.04). Patients with initial infarct volumes <70 cm
3
who recanalized early had the best clinical outcomes (
P
<0.008) with a 64% rate of modified Rankin Scale score ≤2 and the least infarct growth (
P
<0.03) with mean growth of 18 cm
3
.

Conclusion—

This study supports the use of an acute diffusion-weighted imaging lesion volume threshold as an imaging selection criterion for intra-arterial therapy. It also confirms the importance of early reperfusion in selected patients.
Accuracy of Transcranial Doppler Compared With CT Angiography in Diagnosing Arterial Obstructions in Acute Ischemic Strokes
Authors: Brunser Alejandro M. , Lavados Pablo M. , Hoppe Arnold , Lopez Javiera , Valenzuela Marcela , Rivas Rodrigo
Published: April 2009

Background and Purpose—

Patients with acute ischemic stroke and intracranial arterial obstructions have a poor prognosis and a high probability of deteriorating at 24 hours. We aimed to evaluate the diagnostic accuracy of power motion mode Doppler (PMD-TCD) compared with CT angiography as standard in diagnosing intracranial arterial obstructions in patients presenting with ischemic stroke of <24 hours.

Methods—

Consecutive patients presenting with acute ischemic stroke to the emergency department underwent high-resolution brain CT angiography and PMD-TCD within a 6-hour difference.

Results—

A total of 100 patients were included. PMD-TCD demonstrated 34 intracranial occlusions and CTA 33. There were 6 false-positives and 4 false-negative diagnoses with PMD-TCD. PMD-TCD had a positive likelihood ratio of 13.7, a negative likelihood ratio of 0.19, sensitivity of 81.8%, and specificity of 94% for detecting an arterial occlusion in any specific artery. Results for the middle cerebral artery were: positive likelihood ratio 24.6, negative likelihood ratio 0.045, sensitivity 95.6%, and specificity 96.2%. For the anterior circulation, the results were: positive likelihood ratio 18.5, negative likelihood ratio 0, sensitivity 100%, and specificity 94.5%. For the posterior circulation, the results were: positive likelihood ratio >1000, negative likelihood ratio 0.42, sensitivity 57.1%, and specificity 100%. The post-test probability for any occluded artery when PMD-TCD was positive increased for any admission National Institutes of Health Stroke Scale score but was especially remarkable for National Institutes of Health Stroke Scale scores between 7 and 15 points.

Conclusions—

PMD-TCD is valid compared with CT angiography for the diagnosis of arterial occlusions in patients with acute ischemic stroke, especially in middle cerebral artery obstructions.
Effects of Timing and Extent of Smoking, Type of Cigarettes, and Concomitant Risk Factors on the Association Between Smoking and Subclinical Atherosclerosis
Authors: Baldassarre Damiano , Castelnuovo Samuela , Frigerio Beatrice , Amato Mauro , Werba José P. , De Jong Arienne , Ravani Alessio L. , Tremoli Elena , Sirtori Cesare R.
Published: April 2009

Background and Purpose—

The purpose of this study was to evaluate the effects of timing and extent of smoking, type of cigarettes, and concomitant vascular risk factors (VRFs) on the association between smoking and carotid intima-media thickness (C-IMT) in a lipid clinic population.

Methods—

1804 patients (869 men, age 21 to 85 year) participated in the study. Smoking habits were recorded and C-IMTs were measured by B-mode ultrasound. The associations of C-IMT with smoking status (never, former, and current) and with the cigarettes’ content of tar, nicotine, and carbon monoxide (alone or combined to define “light” or “regular” cigarettes) as well as the interactions between smoking status, gender, and VRFs were evaluated before and after adjustment for confounders.

Results—

C-IMT was highest in current smokers, lower in former, and lowest in never smokers. C-IMT of former and current smokers differed only after data adjustment for variables describing the extent and timing of smoking exposure. C-IMT was positively related to the number of pack-years (number of cigarettes smoked per day [cigarettes/d] multiplied by number of years smoked/20) in both former and current smokers. There were no differences in C-IMT between smokers of cigarettes with high or low nicotine, tar, or carbon monoxide content. Both diabetes and hypertension interacted positively with smoking in determining C-IMTs.

Conclusions—

In the present cross-sectional observational investigation, carried out in a cohort of patients attending a lipid clinic, consumption of light cigarettes does not reduce the atherogenic effect of smoking on C-IMT. The number of pack-years, cigarettes/d, and years of smoking are relevant covariates in evaluating the effects of smoking on vascular health. The presence of diabetes or hypertension strengthens the association between smoking and cardiovascular risk.
Transcerebral Exchange Kinetics of Nitrite and Calcitonin Gene-Related Peptide in Acute Mountain Sickness
Authors: Bailey Damian M. , Taudorf Sarah , Berg Ronan M.G. , Jensen Lars T. , Lundby Carsten , Evans Kevin A. , James Philip E. , Pedersen Bente K. , Moller Kirsten
Published: April 2009

Background and Purpose—

High-altitude headache is the primary symptom associated with acute mountain sickness, which may be caused by nitric oxide-mediated activation of the trigeminovascular system. Therefore, the present study examined the effects of inspiratory hypoxia on the transcerebral exchange kinetics of the vasoactive molecules, nitrite (NO
2
•
), and calcitonin gene-related peptide (CGRP).

Methods—

Ten males were examined in normoxia and after 9-hour exposure to hypoxia (12.9% O
2
). Global cerebral blood flow was measured by the Kety-Schmidt technique with paired samples obtained from the radial artery and jugular venous bulb. Plasma CGRP and NO
2
•
were analyzed via radioimmunoassay and ozone-based chemiluminescence. Net cerebral exchange was calculated by the Fick principle and acute mountain sickness/headache scores assessed via clinically validated questionnaires.

Results—

Hypoxia increased cerebral blood flow with a corresponding increase in acute mountain sickness and headache scores (
P
<0.05 vs normoxia). Hypoxia blunted the cerebral uptake of NO
2
•
, whereas CGRP exchange remained unaltered. No relationships were observed between the change (hypoxia–normoxia) in cerebral NO
2
•
or CGRP exchange and acute mountain sickness/headache scores (
P
>0.05).

Conclusion—

These findings argue against sustained trigeminovascular system activation as a significant event in acute mountain sickness.
A Self-Administered Graded Repetitive Arm Supplementary Program (GRASP) Improves Arm Function During Inpatient Stroke Rehabilitation
Authors: Harris Jocelyn E. , Eng Janice J. , Miller William C. , Dawson Andrew S.
Published: April 2009

Background and Purpose—

More than 70% of individuals who have a stroke experience upper limb deficits that impact daily activities. Increased amount of upper limb therapy has positive effects; however, practical and inexpensive methods of therapy are needed to deliver this increase in therapy.

Methods—

This was a multi-site single blind randomized controlled trial to determine the effectiveness of a 4-week self-administered graded repetitive upper limb supplementary program (GRASP) on arm recovery in stroke. 103 inpatients with stroke were randomized to the experimental group (GRASP group, n=53) or the control group (education protocol, n=50). The primary outcome measure was the Chedoke Arm and Hand Activity Inventory (CAHAI), a measure of upper limb function in activities of daily living. Secondary measures were used to evaluate grip strength and paretic upper limb use outside of therapy time. Intention-to-treat analysis was performed. Group differences were tested using analysis of covariance.

Results—

At the end of the 4-week intervention (approximately 7 weeks poststroke), the GRASP group showed greater improvement in upper limb function (CAHAI) compared to the control group (mean difference 6.2; 95% CI: 3.4 to 9.0;
P
<0.001). The GRASP group maintained this significant gain at 5 months poststroke. Significant differences were also found in favor of the GRASP protocol for grip strength and paretic upper limb use. No serious adverse effects were experienced.

Conclusion—

A self-administered homework exercise program provides a cost-, time-, and treatment-effective delivery model for improving upper limb recovery in subacute stroke.
Defining Vasospasm After Subarachnoid Hemorrhage
Authors: Frontera Jennifer A. , Fernandez Andres , Schmidt J. Michael , Claassen Jan , Wartenberg Katja E. , Badjatia Neeraj , Connolly E. Sander , Mayer Stephan A.
Published: April 2009

Background and Purpose—

Vasospasm is an important complication of subarachnoid hemorrhage, but is variably defined in the literature.

Methods—

We studied 580 patients with subarachnoid hemorrhage and identified those with: (1) symptomatic vasospasm, defined as clinical deterioration deemed secondary to vasospasm after other causes were eliminated; (2) delayed cerebral ischemia (DCI), defined as symptomatic vasospasm, or infarction on CT attributable to vasospasm; (3) angiographic spasm, as seen on digital subtraction angiography; and (4) transcranial Doppler (TCD) spasm, defined as any mean flow velocity >120 cm/sec. Logistic regression analysis was performed to test the association of each definition of vasospasm with various hospital complications, and 3-month quality of life (sickness impact profile), cognitive status (telephone interview of cognitive status), instrumental activities of daily living (Lawton score), and death or severe disability at 3 months (modified Rankin scale score 4–6), after adjustment for covariates.

Results—

Symptomatic vasospasm occurred in 16%, DCI in 21%, angiographic vasospasm in 31%, and TCD spasm in 45% of patients. DCI was statistically associated with more hospital complications (N=7; all
P
<0.05) than symptomatic spasm (N=4), angiographic spasm (N=1), or TCD vasospasm (N=1). Angiographic and TCD vasospasm were not related to any aspect of clinical outcome. Both symptomatic vasospasm and DCI were related to reduced instrumental activities of daily living, cognitive impairment, and poor quality of life (all
P
<0.05). However, only DCI was associated with death or severe disability at 3 months (adjusted OR, 2.2; 95% CI, 1.2–3.9;
P
=0.007).

Conclusions—

DCI is a more clinically meaningful definition than either symptomatic deterioration alone or the presence of arterial spasm by angiography or TCD.
Autoregulation in the Posterior Circulation Is Altered by the Metabolic State of the Visual Cortex
Authors: Nakagawa Kazuma , Serrador Jorge M. , LaRose Sarah L. , Moslehi Fatemeh , Lipsitz Lewis A. , Sorond Farzaneh A.
Published: April 2009

Background and Purpose—

Previous studies suggest that dynamic autoregulation in the posterior cerebral artery (PCA) is less efficient compared to the middle cerebral artery (MCA). We examined the role of cerebral vasodilation caused by metabolic activation (ie, visual stimulus) on autoregulatory characteristics in the 2 vascular territories.

Methods—

Blood flow velocity in the PCA and MCA and mean arterial pressure were measured continuously in 45 healthy volunteers (62±3 years) while seated with eyes open. Additional 20 subjects (60±5 years) were examined with eyes closed and open. Autoregulation was assessed using transfer function gains in both the PCA and MCA territories in the low (0.03–0.07 Hz), high (0.07–0.15 Hz), and cardiac (≈1 Hz) frequency ranges.

Results—

With eyes open, gains were significantly higher in the PCA compared to the MCA in the low (PCA: 1.41±0.09 vs MCA: 1.18±0.07;
P
=0.003) and high (PCA: 2.06±0.12 vs MCA: 1.61±0.08;
P
=0.0001) frequencies. Opening eyes increased blood flow velocity and reduced cerebrovascular resistance index in the PCA but not in MCA. This vasodilation in the PCA was associated with increased gain in the low (autoregulatory) frequency, whereas MCA gain did not change (PCA: 0.89±0.14 vs 1.31±0.17, MCA: 1.24±0.16 vs 1.16±0.11;
P
=0.02).

Conclusions—

Dilation of the PCA territory during visual cortex activation resulted in increased PCA transfer function gain without changing MCA gain. Thus, impaired autoregulation in the PCA reported in previous literature is likely the result of metabolic vasodilation and not an inherent difference in the autoregulatory characteristics of the posterior circulation.
Comparison of 10 Perfusion MRI Parameters in 97 Sub-6-Hour Stroke Patients Using Voxel-Based Receiver Operating Characteristics Analysis
Authors: Christensen Søren , Mouridsen Kim , Wu Ona , Hjort Niels , Karstoft Henrik , Thomalla Götz , Röther Joachim , Fiehler Jens , Kucinski Thomas , Østergaard Leif
Published: April 2009

Background and Purpose—

Perfusion-weighted imaging can predict infarct growth in acute stroke and potentially be used to select patients with tissue at risk for reperfusion therapies. However, the lack of consensus and evidence on how to best create PWI maps that reflect tissue at risk challenges comparisons of results and acute decision-making in trials. Deconvolution using an arterial input function has been hypothesized to generate maps of a more quantitative nature and with better prognostic value than simpler summary measures such as time-to-peak or the first moment of the concentration time curve. We sought to compare 10 different perfusion parameters by their ability to predict tissue infarction in acute ischemic stroke.

Methods—

In a retrospective analysis of 97 patients with acute stroke studied within 6 hours from symptom onset, we used receiver operating characteristics in a voxel-based analysis to compare 10 perfusion parameters: time-to-peak, first moment, cerebral blood volume and flow, and 6 variants of time to peak of the residue function and mean transit time maps. Subanalysis assessed the effect of reperfusion on outcome prediction.

Results—

The most predictive maps were the summary measures first moment and time-to-peak. First moment was significantly more predictive than time to peak of the residue function and local arterial input function-based methods (
P
<0.05), but not significantly better than conventional mean transit time maps.

Conclusion—

Results indicated that if a single map type was to be used to predict infarction, first moment maps performed at least as well as deconvolved measures. Deconvolution decouples delay from tissue perfusion; we speculate this negatively impacts infarct prediction.
Advances in Interventional Neuroradiology
Authors: Wakhloo Ajay K. , Deleo Michael J. , Brown Martin M.
Published: April 2009

In 2008 we witnessed a rapid advancement in stent technology, which is reflected in the high number of case reports, publications of case series, and randomized trials. Stents not only served for a combined intrasaccular and extrasaccular treatment of challenging aneurysms but also assisted the revascularization in acute and chronic ischemic conditions of the neurovascular system. Although a self-expanding nitinol semiopen cell stent is currently used for intracranial occlusive disease, a new retrievable closed-cell designed stent is widely used for aneurysms because of its easy delivery through a microcatheter in frequently tortuous head and neck as well as cerebrovascular circulation (
Figure 1
). However, despite numerous publications in the field, the widespread acceptance of the use of stents to routinely treat carotid stenosis awaits the results of the multicenter randomized clinical trials that should be available in 2009. The role of interventional neuroradiology in the treatment of acute ischemic stroke continues to expand and excite interest.

Figure 1.
Intracranial nitinol self-expanding stents used for endovascular treatment of aneurysm in conjunction with coil embolization. A, Closed cell design with flaring ends (Enterprise VRD; Codman Neurovascular, Raynham, MA). B, Semiopen cell design (Neuroform; Boston Scientific, Natick, MA).
Cultural Differences in Allocation of Attention in Visual Information Processing
Authors: Boduroglu Aysecan , Shah Priti , Nisbett Richard E.
Published: April 2009

Previous research has shown that when processing visual scenes, Westerners attend to salient objects and East Asians attend to the relationships between focal objects and background elements. It is possible that cross-cultural differences in attentional allocation contribute to these earlier findings. In this article, the authors investigate cultural differences in attentional allocation in two experiments, using a visual change detection paradigm. They demonstrate that East Asians are better than Americans at detecting color changes when a layout of a set of colored blocks is expanded to cover a wider region and worse when it is shrunk. East Asians are also slower than Americans are at detecting changes in the center of the screen. The data suggest that East Asians allocate their attention more broadly than Americans. The authors consider potential factors that may contribute to the development of such attention allocation differences.
Teachers Closing the Discipline Gap in an Urban Middle School
Authors: Monroe Carla R.
Published: April 2009

This study focuses on student discipline as related to the perceptions, work, and backgrounds of effective Black and White teachers. The article expands current knowledge by reporting findings from a case study of 4 teachers (2 African Americans and 2 Whites) employed in an urban, predominately African American middle school. Interviews, field visits, and documents were analyzed according to guidelines created by Miles and Huberman (1994) and collectively point to four themes: (a) learning-based perceptions of student behavior, (b) the role of preservice teacher preparation, (c) the influence of remembered teachers and teacher mentors, and (d) outreach efforts to students' parents and families. The study's implications for future scholarship and practice are considered.
A Situation's First Powers Are Attracting Volunteers and Selecting Participants: A Reply to Haney and Zimbardo (2009)
Authors: McFarland Sam , Carnahan Thomas
Published: April 2009

This reply addresses three issues raised by C. Haney and P. G. Zimbardo (2009) in their critique of T. Carnahan and S. McFarland (2007). First, it clarifies Carnahan and McFarland's appreciation of the Stanford Prison Experiment (SPE) but suggests that as a model for the power of situations, the SPE does not adequately consider self-selection and selection by others, both based in part in personal dispositions. Second, it comments briefly on Haney and Zimbardo's critique of Carnahan and McFarland's study and of its applicability to the SPE. Finally, it illustrates the importance of selection and self-selection for situations of torture and suggests their importance for many situations.
Early Adolescent Romantic Partner Status, Peer Standing, and Problem Behaviors
Authors: Miller Shari , Lansford Jennifer E. , Costanzo Philip , Malone Patrick S. , Golonka Megan , Killeya-Jones Ley A.
Published: April 2009

This study examined associations among early adolescent romantic relationships, peer standing, problem behaviors, and gender as a moderator of these associations, in a sample of 320 seventh-grade students. Popular and controversial status youth were more likely to have a romantic partner, whereas neglected status youth were less likely to have a romantic partner. Similarly, youth perceived as conventional and unconventional leaders were also more likely to have a romantic partner than were non-leaders. Youth who had a romantic partner drank more alcohol and were more aggressive than were youth who did not have a romantic partner. Among those youth who had romantic partners, those who reported having more deviance-prone partners were themselves more likely to use alcohol and to be more aggressive, and those who engaged in deviant behavior with their partners used more alcohol. However, these associations varied somewhat by gender. These findings underscore the salience of early romantic partner relationships in the adjustment of early adolescents.
Interobserver Reliability of Neovascularization Score Using Power Doppler Ultrasonography in Midportion Achilles Tendinopathy
Authors: Sengkerij Pieter M. , de Vos Robert-Jan , Weir Adam , van Weelde Bert J. G. , Tol Johannes L.
Published: April 2009

Background

Power Doppler ultrasonography is widely used to examine neovascularization in midportion Achilles tendinopathy. The reliability of the grading of the degree of neovascularization has not been examined previously.

Hypothesis

Power Doppler ultrasonography can be performed with a high interobserver reliability to determine the neovascularization score in patients with midportion Achilles tendinopathy.

Study Design

Case control study (diagnosis); Level of evidence, 4.

Methods

Thirty-three symptomatic and 17 asymptomatic Achilles tendons from 25 consecutive patients were included for ultrasound examination. Victorian Institute of Sport Assessment–Achilles score was used to assess the severity of the Achilles tendinopathy. Each tendon was scored twice by different radiologists using the modified Öhberg score for neovascularization.

Results

The intraclass correlation coefficient for interobserver reliability was 0.85. Neovascularization was observed in 70% (23/33) of the symptomatic tendons and in 29% (5/17) of the asymptomatic tendons. The Spearman correlation coefficient between the Victorian Institute of Sport Assessment–Achilles score and the degree of neovascularization was −0.16 (P =. 10).

Conclusion

An excellent interobserver reliability was found for determining the degree of neovascularization on power Doppler ultrasonography examination. Neovessels were present in a majority of symptomatic tendons. The severity of symptoms was not correlated with the neovascularization score.

Clinical Relevance

Power Doppler ultrasonography is widely used to evaluate tendinopathy without knowledge of the difference in observations between several testers. Interobserver reliability of the evaluation of the degree of neovascularization in chronic midportion Achilles tendinopathy is excellent.
The Shoulders of Professional Beach Volleyball Players
Authors: Lajtai Georg , Pfirrmann Christian W. A. , Aitzetmüller Gernot , Pirkl Christof , Gerber Christian , Jost Bernhard
Published: April 2009

Background

Beach volleyball is an Olympic overhead sport. It is not well known which clinical and imaging findings are normal and which are associated with symptoms.

Hypothesis

There are typical clinical and imaging findings in the hitting shoulders of fully competitive professional beach volleyball players, as compared with their nonhitting shoulders.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

During the Beach Volleyball Grand Slam Tournament in Klagenfurt, Austria, 84 professional players (54 men, 30 women) underwent a questionnaire-based interview and a complete physical examination, including scoring and sonography of both shoulders. Twenty-nine players had shoulder MRIs.

Results

The mean age of the athletes was 28 years. Atrophy of the infraspinatus muscle was found in 30% of the hitting shoulders, and it was not typically recognized by the players. The absolute Constant score was significantly lower in the hitting shoulder (87 versus 93 points, P < .0001). Average external rotation strength was decreased in the hitting shoulder (8.2 versus 9.5 kg, P < .0001). There were more abnormalities on the sonography of the hitting shoulder (1.7 versus 0.4, P < .0001) and in the same shoulders on MRI than on sonography (P = .0231). Compression of the suprascapular nerve was not observed. Pain in the hitting shoulder was present in 63% of the players, without clear correlations to the investigated clinical and imaging parameters.

Conclusion

The prevalence of infraspinatus muscle atrophy in professional beach volleyball players is 30%. The typical, fully competitive player has subjectively unrecognized decreased strength of external rotation and frequent unspecific shoulder pain. Therefore, abnormal clinical and imaging findings in the beach volleyball player should be interpreted with care.
Psychological Health and Meaning in Life
Authors: Dunn Marianne G. , O'Brien Karen M.
Published: April 2009

This study examined the relative contributions of (a) gender, (b) perceived stress, (c) social support from family and significant other, and (d) positive and negative dimensions of religious coping to the prediction of the psychological health and meaning in life among 179 Central American immigrants from El Salvador and Guatemala. Findings reveal that greater perceived stress by Latinas/Latinos was predictive of psychological health and meaning in life, while social support from a significant other also explained variance in meaning in one's life. Negative religious coping, specifically reappraisal of God's powers, was predictive of search for meaning in one's life.
Coma Blisters in 2 Children on Anticonvulsant Medication
Authors: Basu Anna , Brown Sara , Kirkham Nigel , Ramesh Venkateswaran , Leech Suzy , Devlin Anita
Published: April 2009

Blister formation and eccrine sweat gland necrosis have been recognized to occur in states of impaired consciousness and were first reported following barbiturate intoxication. Their etiology is complex and cannot simply be explained by pressure effects. Now that barbiturates are less frequently used, clinicians are likely to be less aware of the phenomenon of coma blister formation; however, newer drugs have also been associated with the occurrence of coma blisters. We describe 2 new associations of coma blisters and anticonvulsants in children. In the first child, blisters recurred on multiple occasions along with obtundation and edema. Our aims are to alert clinicians to the occurrence of coma blisters in children sedated on anticonvulsant medications and to report the new finding of recurrent coma blisters.
MoSeS
Authors: Birkin Mark , Turner Andy , Wu Belinda , Townend Paul , Arshad Junaid , Xu Jie
Published: April 2009

The authors present an architecture for simulation modeling using the resources of grid computing. The use of the grid provides access to the substantial data storage and processing power, which are necessary to translate such models from computational tools into genuine planning aids. As well as providing access to virtualized compute resources, the architecture allows customized applications to meet the needs of an array of potential user organizations. A number of key obstacles in the deployment and integration of e-Science services are identified. These include the high computational costs of simulation modeling at the microscale for typical ‘‘what if’’ scenario questions in research and policy settings; the management and technical issues relating to security in licensing common data sources; sociocultural, legal, and administrative restrictions on the privacy of individual-level response data; and the slow development and lack of uptake of agreed standards such as JSR-168 compliant portlets in the construction of useable applications.
The Janus-Faced Effects of Hypoxia on Astrocyte Function
Authors: Vangeison Grace , Rempe David A.
Published: April 2009

Astrocytes are increasingly recognized for their impact on neuronal function and viability in health and disease. Hypoxia has Janus-faced influences on astrocytes and their ability to support neuronal viability. For example, hypoxia induces astrocyte-dependent protection of neurons following hypoxia preconditioning. Yet, hypoxia induces processes in astrocytes that augment neuronal death in other situations, such as the coincidence of hypoxia with inflammatory signaling. A complex array of gene expression is induced by hypoxia within astrocytes and neurons through multiple transcription factors and intracellular molecular pathways. The hypoxia inducible factors (HIFs) are transcription factors that are likely instrumental in orchestrating adaptive and pathological functions of astrocytes. As such, the HIFs are postulated to mediate both adaptive and pathological functions during hypoxia/ ischemia. Identifying the conditions under which hypoxia induces signaling in astrocytes that alters autonomous or neuronal survival will undoubtedly have important implications regarding the development of new strategies for stroke treatment.
Is Progesterone a Candidate Neuroprotective Factor for Treatment following Ischemic Stroke?
Authors: Gibson Claire L , Coomber Ben , Rathbone James
Published: April 2009

Gender differences in stroke outcome have implicated steroid hormones as potential neuroprotective candidates. However, no clinical trials examining hormone replacement therapy on outcome following ischemic stroke have investigated the effect of progesterone-only treatment. In this review the authors examine the experimental evidence for the neuroprotective potential of progesterone and give an insight into potential mechanisms of action following ischemic stroke. To date, 17 experimental studies have investigated the neuroprotective potential of progesterone for ischemic stroke in terms of ability to both reduce cell loss and increase functional outcome. Of these 17 published studies the majority reported a beneficial effect with three studies reporting a nil effect and only one study reporting a negative effect. However, there are important issues that the authors address in this review in terms of the methodological quality of studies in relation to the STAIR recommendations. In terms of the proposed mechanisms of progesterone neuroprotection we show that progesterone is versatile and acts at multiple targets to facilitate neuronal survival and minimize cell damage and loss. A large amount of experimental evidence indicates that progesterone is a neuroprotective candidate for ischemic stroke; however, to progress to clinical trial a number of key experimental studies remain outstanding.
Absent Memory, Family Secrets, Narrative Inheritance
Authors: McNay Margaret
Published: April 2009

Narratives are essential to the construction of personal identity, relationships, and fully actualized lives. Narrative inheritance consists of the stories and family lore that parents and other relatives pass on to children about the family. The article describes two belatedly acquired narratives of inheritance: the author’s own and that of Harold Goodall. The author applies the notion of “absent memory” to the family secrets that underlie these narratives and reflect on questions raised by such secrets—and by incomplete narrative inheritances—for the children burdened with them.
The Effect of Density Zoning on Racial Segregation in U.S. Urban Areas
Authors: Rothwell Jonathan , Massey Douglas S.
Published: April 2009

The authors argue that anti-density zoning increases Black residential segregation in U.S. metropolitan areas by reducing the quantity of affordable housing in White jurisdictions. Drawing on census data and local regulatory indicators compiled by Pendall, the authors estimate a series of regression models to measure the effect of maximum density zoning on Black segregation. Results estimated using ordinary least squares indicate a strong and significant cross-sectional relationship between low-density zoning and racial segregation, even after controlling for other zoning policies and a variety of metropolitan characteristics, a relationship that persists under two-stage least squares estimation. Both estimation strategies also suggest that anti-density zoning inhibits desegregation over time.
From “Politico-Scientists” to Democratizing Science Movements
Authors: McCormick Sabrina
Published: April 2009

The Committee for Nuclear Information (CNI) was one of the first movements to translate expert knowledge to the public. It was led by “politico-scientists” who meant to advance an ethics of science by contributing to public understanding. Since then, citizens have taken research into their own hands, using it to frame issues, challenge corporate practices, and change policy. Movement methods that respond to consistent activist concerns about science are reflected in “democratizing science movements” (DSMs) that have grown, expanded, and changed in the past 50 years. This article compares the CNI to the Campaign for Safe Cosmetics, a group of organizations that have critiqued the hazardous ingredients in personal care products. The aim is to update our understanding of how movements use science to protect health and improve the environment since the CNI. Like CNI, Campaign activists have used science to educate the public about hazardous exposures; however, the Campaign reflects that over time, lay people have become more central to scientific production as well as more able to use it without the assistance of experts. It is argued that in Commoner's time scientists focused on translating results and meanings for lay audiences whereas today, movements use science to heighten the political nature of the issue through reframing.
As Easy as Pie
Authors: Nathanson Elizabeth
Published: April 2009

This article examines how the media define women's experience of time in the postfeminist context through analysis of the popular Food Network program 30 Minute Meals. In a context in which women attempt to “have it all,” the media expose anxieties about and offer solutions for how women should balance home and work demands. Contemporary representations of domesticity on television present the home as radically affected by the temporal logic of the working world. By interrogating 30 Minute Meals's real-time narrative structure alongside the marketing strategies of stores like Crate and Barrel, this article argues that postfeminist media propose contradictory remedies to the contemporary “time crunch” in the form of rational and efficient time management and nostalgia for an imagined past in which women had endless amounts of time. Studying how the media represent women's time is crucial to understanding definitions of femininity and women's labor and leisure in the postfeminist context.