Dealkylation of Poly(methyl methacrylate) by TiCl4 Vapor Phase Infiltration (VPI) and the Resulting Chemical and Thermophysical Properties of the Hybrid Material.

This study examines the chemical reaction pathways for vapor phase infiltration (VPI) of TiCl4 into poly(methyl methacrylate) (PMMA). VPI is a processing method that transforms organic polymers into organic-inorganic hybrid materials with new properties of interest for microelectronic patterning, technical textiles, and chemical separations. Understanding the fundamental chemical mechanisms of the VPI process is essential for establishing approaches to design the chemical structure and properties of these hybrid materials. While prior work has suggested that TiCl4 infiltration into PMMA does not disrupt the polymer's carbonyl bond, a clear reaction mechanism has yet to be proposed. Here, we present a detailed X-ray photoelectron spectroscopy study that presents evidence for a concerted reaction mechanism that involves TiCl4 coordinating with the PMMA's ester group to dealkylate the methyl side group, creating a chloromethane byproduct and primary chemical bonds between the organic and inorganic components of the hybrid material. Additional spectroscopy, quartz crystal microbalance gravimetry, and thermophysical and chemical property measurements of this material, including solubility studies and thermal expansion measurements, provide further evidence for this chemical reaction pathway and the subsequent creation of inorganic cross-links that network these TiOx-PMMA hybrid materials.

Correlation Between Maxillary Anterior Teeth and Common Facial Measurements.

Background: The symmetry between maxillary anterior teeth and the face holds significant importance. This study assessed and analyzed the relationship between facial parameters and anterior teeth in the maxillary arch of male and female subjects. Specifically, individual width and combined width (CW) measurements of the maxillary anterior teeth were investigated. Methods: This study involved a total of 150 dentate Yemeni subjects (74 men and 76 women), whose ages ranged from 18 years old to 30 years old. A maxillary cast was created, and two digital photographs of the face of each subject were taken and analyzed. Digital calipers and AutoCAD were used to gather measurement data of the dental parameters (intercanthal distance [ICD], interpupillary distance [IPD], interalar width [IAW], intercommissural width [ICW], and bizygomatic width [BZW]) and facial parameters (profile distance). Results: Significant correlations were found for the following: IPD and width of six maxillary anterior teeth of each of the study subjects; ICD and their central incisors; and BZW and their canine width measurements. In contrast, IAW and ICW were not correlated with all tooth measurements. Linear regression findings showed that the CW measurement of the four incisors was significantly correlated with all facial parameter measurements, excluding the ICW and IAW in females and the IAW, ICW, and profile distance in males. Conclusion: The IPD and ICD of males and females may be used to determine their CW measurements. The BZW and IPD of males can be used to take precise anthropological measurements of the width of the central canines and incisors. Meanwhile, the IPD distance of females can be used to assess the central and lateral incisor widths.

Cellulose Nanofibril Stabilized Pickering Emulsion Templated Aerogel with High Oil Absorption Capacity.

Nanocellulose-based aerogels, featuring a three-dimensional porous structure, are considered as a desirable green absorbent because of their exceptional absorption performance as well as the abundance and renewability of the raw material. However, these aerogels often require hydrophobic modification or carbonization, which is often environmentally harmful and energy-intensive. In this study, we introduce a Pickering-emulsion-templating approach to fabricate a cellulose nanofibril (CNF) aerogel with a hierarchical pore structure, allowing for high oil absorption capacity. n-Hexane-CNF oil-in-water Pickering emulsions are prepared as an emulsion template, which is further lyophilized to create a hollow microcapsule-based CNF (HM-CNF) aerogel with a density ranging from 1.3 to 6.1 mg/cm3 and a porosity of ≥99.6%. Scanning electron microscopy and Brunauer-Emmett-Teller analyses reveal the HM-CNF aerogel's hierarchical pore structure, originating from the CNF Pickering emulsion template, and also confirm the aerogel's very high surface area of 216.6 m2/g with an average pore diameter of 8.6 nm. Furthermore, the aerogel exhibits a maximum absorption capacity of 354 g/g and 166 g/g for chloroform and n-hexadecane, respectively, without requiring any surface modification or chemical treatment. These combined findings highlight the potential of the Pickering-emulsion-templated CNF aerogel as an environmentally sustainable and high-performance oil absorbent.

Interpreting inorganic compositional depth profiles to understand the rate-limiting step in vapor phase infiltration processes.

Vapor phase infiltration (VPI) is a post-polymerization modification technique that infuses inorganics into polymers to create organic-inorganic hybrid materials with new properties. Much is yet to be understood about the chemical kinetics underlying the VPI process. The aim of this study is to create a greater understanding of the process kinetics that govern the infiltration of trimethyl aluminum (TMA) and TiCl4 into PMMA to form inorganic-PMMA hybrid materials. To gain insight, this paper initially examines the predicted results for the spatiotemporal concentrations of inorganics computed from a recently posited reaction-diffusion model for VPI. This model provides insight on how the Damköhler number (reaction versus diffusion rates) and non-Fickian diffusional processes (hindering) that result from the material transforming from a polymer to a hybrid can affect the evolution of inorganic concentration depth profiles with time. Subsequently, experimental XPS depth profiles are collected for TMA and TiCl4 infiltrated PMMA films at 90 °C and 135 °C. The functional behavior of these depth profiles at varying infiltration times are qualitatively compared to various computed predictions and conclusions are drawn about the mechanisms of each of these processes. TMA infiltration into PMMA appears to transition from a diffusion-limited process at low temperatures (90 °C) to a reaction-limited process at high temperatures (135 °C) for the film thicknesses investigated here (200 nm). While TMA appears to fully infiltrate these 200 nm PMMA films within a few hours, TiCl4 infiltration into PMMA is considerably slower, with full saturation not occurring even after 2 days of precursor exposure. Infiltration at 90 °C is so slow that no clear conclusions about mechanism can be drawn; however, at 135 °C, the TiCl4 infiltration into PMMA is clearly a reaction-limited process, with TiCl4 permeating the entire thickness (at low concentrations) within only a few minutes, but inorganic loading continuously increasing in a uniform manner over a course of 2 days. Near-surface deviations from the uniform-loading expected for a reaction-limited process also suggest that diffusional hindering is high for TiCl4 infiltration into PMMA. These results demonstrate a new, ex situ analysis approach for investigating the rate-limiting process mechanisms for vapor phase infiltration.

A sorbent containing pH-responsive chelating residues of aspartic and maleic acids for mitigation of toxic metal ions, cationic, and anionic dyes.

t-Butyl hydroperoxide-initiated cycloterpolymerization of diallylaminoaspartic acid hydrochloride [(CH2[double bond, length as m-dash]CHCH2)2NH+CH(CO2H)CH2CO2H Cl-] (I), maleic acid (HO2CH[double bond, length as m-dash]CHCO2H) (II) and cross-linker tetraallylhexane-1,6-diamine dihydrochloride [(CH2[double bond, length as m-dash]CHCH2)2NH+(CH2)6NH+ (CH2CH[double bond, length as m-dash]CH2)2 2Cl-] (III) afforded a new pH-responsive resin (IV), loaded with four CO2H and a chelating motif of NH+⋯CO2 - in each repeating unit. The removal of cationic methylene blue (MB) (3000 ppm) at pH 7.25 and Pb(ii) (200 ppm) at pH 6 by IV at 298, 313, and 328 K followed second-order kinetics with E a of 33.4 and 40.7 kJ mol-1, respectively. Both MB and Pb(ii) were removed fast, accounting for 97.7% removal of MB within 15 min at 313 K and 94% of Pb(ii) removal within 1 min. The super-adsorbent resin gave respective q max values of 2609 mg g-1 and 873 mg g-1 for MB and Pb(ii). IV was also found to trap anionic dyes; it removed 91% Eriochrome Black T (EBT) from its 50 ppm solutions at pH 2. The resin was found to be effective in reducing priority metal contaminants (like Cr, Hg, Pb) in industrial wastewater to sub-ppb levels. The synthesis of the recyclable resin can be easily scaled up from inexpensive starting materials. The resin has been found to be better than many recently reported sorbents.

Coronavirus disease 2019 and stroke in Iran: a case series and effects on stroke admissions.

OBJECTIVE: The coronavirus disease 2019 pandemic has affected healthcare systems around the globe and massively impacted patients with various non-infectious, life-threatening conditions. Stroke is a major neurological disease contributing to death and disability worldwide, and is still an ongoing issue during the pandemic. Here we investigate the impact of the coronavirus disease 2019 outbreak on stroke manifestations, treatment courses, the outcome of stroke patients, and the hospitalization rate in a referral center for stroke management in Tehran, Iran. METHODS: We extracted data regarding 31 stroke patients (10 patients with laboratory-confirmed coronavirus disease 2019) and compared the demographic and pathological characteristics of the patients with or without coronavirus disease 2019 infection. The association of demographic/pathological characteristics of stroke patients during the coronavirus disease 2019 pandemic and a corresponding period during the previous year (49 patients) and an earlier period during the same year as the pandemic (50 patients) was also evaluated. RESULTS: The absolute number of admissions decreased about 40% during the coronavirus disease 2019 pandemic. Except for the stroke severity (P = 0.002), there were no significant changes in the demographic and pathological characteristics of the stroke patients during the three studied periods. A significantly higher mean of age (75.60 ± 9.54 versus 60.86 ± 18.45; P = 0.007), a significant difference in the type of stroke (P = 0.046), and significantly higher stroke severity (P = 0.024) were observed in stroke patients with coronavirus disease 2019 compared with those of stroke patients without coronavirus disease 2019. Treatment approaches, duration of hospitalization, and mortality rates did not differ significantly. CONCLUSIONS: This report shows that the pandemic caused the number of acute stroke admissions to plummet compared to other periods. Although the pandemic did not affect the treatment plans and care of the patients, stroke cases with coronavirus disease 2019 had higher age, more large vessel ischemic stroke, and more severe stroke. Further studies are urgently needed to realize the probable interaction of the coronavirus disease 2019 pandemic and the neurologic disease.

Design and Synthesis of a Dual-Purpose Superadsorbent Containing a High Density of Chelating Motifs for the Fast Mitigation of Methylene Blue and Pb(II).

Maleic acid underwent alternate copolymerization with diallylaminomethylphosphonic acid·HCl [(CH2=CHCH2)2NH+CH2PO3H2 Cl-] and a cross-linker to give a new pH-responsive resin. Methylene blue (MB) removal from its 3000 ppm solution by the resin at pH 7 followed second-order kinetics with an E a of 34.8 kJ mol-1. MB removal was achieved very fast (10 min), attaining over 98.5% at 328 K. The q e obtained using MB concentrations in the range 100-8000 ppm fitted the Langmuir nonlinear isotherm model to give ΔG o, ΔH o, and ΔS o values of ≈ -21 kJ, 36.5 kJ mol-1, and 185 J mol-1 K-1, respectively. The resin is a superadsorbent with a q max value of 2445 mg g-1. The adsorbent also removed 97% Pb(II) within 5 min from its 10 000 ppb solution. The resin reduced the Pb(II) concentration from 200 to 3.8 ppb. The resin also demonstrated its ability to remove contaminants from industrial wastewater, reducing priority metal contaminants to ppb and sub-ppb levels. The resin can be recycled with stable efficiency. The outstanding performance places the resin in a top position in a list of recently reported sorbents.

Time for a Time Window Extension: Insights from Late Presenters in the ESCAPE Trial.

BACKGROUND AND PURPOSE: The safety and efficacy of endovascular therapy for large-artery stroke in the extended time window is not yet well-established. We performed a subgroup analysis on subjects enrolled within an extended time window in the Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) trial. MATERIALS AND METHODS: Fifty-nine of 315 subjects (33 in the intervention group and 26 in the control group) were randomized in the ESCAPE trial between 5.5 and 12 hours after last seen healthy (likely to have groin puncture administered 6 hours after that). Treatment effect sizes for all relevant outcomes (90-day mRS shift, mRS 0-2, mRS 0-1, and 24-hour NIHSS scores and intracerebral hemorrhage) were reported using unadjusted and adjusted analyses. RESULTS: There was no evidence of treatment heterogeneity between subjects in the early and late windows. Treatment effect favoring intervention was seen across all clinical outcomes in the extended time window (absolute risk difference of 19.3% for mRS 0-2 at 90 days). There were more asymptomatic intracerebral hemorrhage events within the intervention arm (48.5% versus 11.5%, P = .004) but no difference in symptomatic intracerebral hemorrhage. CONCLUSIONS: Patients with an extended time window could potentially benefit from endovascular treatment. Ongoing randomized controlled trials using imaging to identify late presenters with favorable brain physiology will help cement the paradigm of using time windows to select the population for acute imaging and imaging to select individual patients for therapy.

Cerebral Perfusion Pressure is Maintained in Acute Intracerebral Hemorrhage: A CT Perfusion Study.

BACKGROUND AND PURPOSE: Although blood pressure reduction has been postulated to result in a fall in cerebral perfusion pressure in patients with intracerebral hemorrhage, the latter is rarely measured. We assessed regional cerebral perfusion pressure in patients with intracerebral hemorrhage by using CT perfusion source data. MATERIALS AND METHODS: Patients with acute primary intracerebral hemorrhage were randomized to target systolic blood pressures of <150 mm Hg (n = 37) or <180 mm Hg (n = 36). Regional maps of cerebral blood flow, cerebral perfusion pressure, and cerebrovascular resistance were generated by using CT perfusion source data, obtained 2 hours after randomization. RESULTS: Perihematoma cerebral blood flow (38.7 ± 11.9 mL/100 g/min) was reduced relative to contralateral regions (44.1 ± 11.1 mL/100 g/min, P = .001), but cerebral perfusion pressure was not (14.4 ± 4.6 minutes(-1) versus 14.3 ± 4.8 minutes(-1), P = .93). Perihematoma cerebrovascular resistance (0.34 ± 0.11 g/mL) was higher than that in the contralateral region (0.30 ± 0.10 g/mL, P < .001). Ipsilateral and contralateral cerebral perfusion pressure in the external (15.0 ± 4.6 versus 15.6 ± 5.3 minutes(-1), P = .15) and internal (15.0 ± 4.8 versus 15.0 ± 4.8 minutes(-1), P = .90) borderzone regions were all similar. Borderzone cerebral perfusion pressure was similar to mean global cerebral perfusion pressure (14.7 ± 4.7 minutes(-1), P ≥ .29). Perihematoma cerebral perfusion pressure did not differ between blood pressure treatment groups (13.9 ± 5.5 minutes(-1) versus 14.8 ± 3.4 minutes(-1), P = .38) or vary with mean arterial pressure (r = -0.08, [-0.10, 0.05]). CONCLUSIONS: Perihematoma cerebral perfusion pressure is maintained despite increased cerebrovascular resistance and reduced cerebral blood flow. Aggressive antihypertensive therapy does not affect perihematoma or borderzone cerebral perfusion pressure. Maintenance of cerebral perfusion pressure provides physiologic support for the safety of blood pressure reduction in intracerebral hemorrhage.

Prevalence and treatment of "balloon-uncrossable" coronary chronic total occlusions.

BACKGROUND: The frequency and outcomes of "balloon-uncrossable" coronary chronic total occlusions (CTOs) have received limited study. METHODS: We retrospectively examined 373 consecutive CTO percutaneous coronary interventions (PCIs) performed at our institution between 2005 and 2013 to determine the frequency and treatment of balloon-uncrossable CTOs. RESULTS: Mean age was 63.7 ± 8.3 years and 98.9% of the patients were men. Twenty-four patients (6.4%, 95% confidence intervals 4.2% to 9.4%) were found to have a balloon-uncrossable CTO. Compared to the other CTO PCI patients, those with balloon-uncrossable CTOs had similar clinical and angiographic characteristics. Successful crossing of the balloon-uncrossable CTO was achieved in 22 of 24 patients (91.7%) using a variety of techniques, such as successive balloon inflations (43.5%), microcatheter advancement (21.7%), laser (8.7%), techniques that increase guide catheter support (13.0%), and subintimal lesion crossing (13.0%). Patients with balloon-uncrossable CTOs had longer procedure time (184.5 ± 77.9 vs 134.0 ± 69.0 min, P<.01), fluoroscopy time (55.2 ± 24.9 vs 37.9 ± 20.8 min, P<.01), and received high contrast volume (404.4 ± 137.9 vs 351.7 ± 138.5 mL, P=.08), but had similar incidence of major complications (8.3% vs 3.2%, P=.25) as compared with patients who did not have balloon-uncrossable CTOs. CONCLUSION: Balloon-uncrossable CTOs are encountered in 6.4% of contemporary CTO PCIs and can be successfully treated in most patients using a variety of techniques.

Frequency and outcomes of aortocoronary dissection during percutaneous coronary intervention of chronic total occlusions: a case series and systematic review of the literature.

BACKGROUND: Aortocoronary dissection can complicate percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs). METHODS: We retrospectively examined the frequency and outcomes of aortocoronary dissection among 336 consecutive CTO PCIs performed at our institution between 2005 and 2012 and performed a systematic review of the published literature. RESULTS: Aortocoronary dissection occurred in six patients (1.8%, 95% confidence intervals 0.7%, 3.8%). All aortocoronary dissections occurred in the right coronary artery (CTO target vessel in five patients and donor vessel in one patient). The baseline clinical characteristics of patients with and without aortocoronary dissection were similar. Compared to patients without, those with aortocoronary dissection were more likely to undergo crossing attempts using the retrograde approach (25% vs. 67%, P = 0.036) and experience a major complication (2.4% vs. 33.3%, P = 0.008). Technical and procedural success rates were similar in both groups. Of the six patients with aortocoronary dissection one underwent emergency coronary bypass graft surgery (CABG), four were treated with ostial stenting, and one was treated conservatively without subsequent adverse clinical outcomes. Systematic literature review provided 107 published cases of aortocoronary dissection during PCI, that occurred mainly in the right coronary artery (74.8%) and were treated with stenting (49.5%), emergency CABG (29%), or conservatively (21.5%). CONCLUSIONS: Aortocoronary dissection is an infrequent complication of CTO PCI and although it can be treated with stents in most patients, it may infrequently require emergency CABG.

NeuroThera® Efficacy and Safety Trial-3 (NEST-3): a double-blind, randomized, sham-controlled, parallel group, multicenter, pivotal study to assess the safety and efficacy of transcranial laser therapy with the NeuroThera® Laser System for the treatment of acute ischemic stroke within 24 h of stroke onset.

RATIONALE: Transcranial laser therapy is undergoing clinical trials in patients with acute ischemic stroke. The NeuroThera® Efficacy and Safety Trial-1 was strongly positive for 90-day functional benefit with transcranial laser therapy, and post hoc analyses of the subsequent NeuroThera® Efficacy and Safety Trial-2 trial suggested a meaningful beneficial effect in patients with moderate to moderately severe ischemic stroke within 24 h of onset. These served as the basis for the NeuroThera® Efficacy and Safety Trial-3 randomized controlled trial. AIM: The purpose of this pivotal study was to demonstrate safety and efficacy of transcranial laser therapy with the NeuroThera® Laser System in the treatment of subjects diagnosed with acute ischemic stroke. DESIGN: NeuroThera® Efficacy and Safety Trial-3 is a double-blind, randomized, sham-controlled, parallel group, multicenter, pivotal study that will enroll 1000 subjects at up to 50 sites. All subjects will receive standard medical management based on the American Stroke Association and European Stroke Organization Guidelines. In addition to standard medical management, both groups will undergo the transcranial laser therapy procedure between 4·5 and 24 h of stroke onset. The study population will be randomized into two arms: the sham control group will receive a sham transcranial laser therapy procedure and the transcranial laser therapy group will receive an active transcranial laser therapy procedure. The randomization ratio will be 1:1 and will be stratified to ensure a balanced subject distribution between study arms. STUDY OUTCOMES: The primary efficacy end point is disability at 90 days (or the last rating), as assessed on the modified Rankin Scale, dichotomized as a success (a score of 0-2) or a failure (a score of 3 to 6).

Body Mass Index and Acute Ischemic Stroke Outcomes.

Background The impact of body mass index on acute ischemic stroke outcomes is unclear. Aims and/or hypothesis We sought to determine the effect of body mass index on short-term (90 days) acute ischemic stroke outcomes. Methods Data were extracted for patients with acute ischemic stroke and records of body mass index at baseline from the Virtual International Stroke Trials Archive database. Multivariate logistic regression and Cox proportional hazard analysis were used to analyze effect of body mass index on poor functional outcome (modified Rankin Scale >2) and mortality, respectively, within 90 days of stroke's onset. Results Of the 4811 patients (mean age 68·8 ± 12·2 years) included in the study, 2002 (41·6%) were overweight, and 1095 (22·8%) were obese. Overweight (body mass index 25-29·9 kg/m2) was associated with decreased mortality (hazard ratios 0·59; 95% confidence interval 0·51-0·68; P < 0·01) and decrease in poor functional outcome (odds ratio 0·74; 95% confidence interval 0·64-0·85; P < 0·01) following acute ischemic stroke. The association of body mass index with stroke outcomes was dependent on age, gender, and use of thrombolytic therapy. Conclusions Being overweight or obese is associated with a better functional outcome and reduced mortality in patients of acute ischemic stroke. However, the definition of an 'optimal' body mass index, in relation to stroke outcomes, may be affected by age, gender, and use of thrombolytic therapy.

Reduced mortality and severe disability rates in the SENTIS trial.

BACKGROUND AND PURPOSE: The Safety and Efficacy of NeuroFlo Technology in Ischemic Stroke trial showed a trend for reduced all-cause mortality and positive secondary safety end point outcomes. We present further analyses of the mortality and severe disability data from the Safety and Efficacy of NeuroFlo Technology in Ischemic Stroke trial. MATERIALS AND METHODS: The Safety and Efficacy of NeuroFlo Technology in Ischemic Stroke trial was a multicenter, randomized, controlled trial that evaluated the safety and effectiveness of the NeuroFlo catheter in patients with stroke. The current analysis was performed on the as-treated population. All-cause and stroke-related mortality rates at 90 days were compared between groups, and logistic regression models were fit to obtain ORs and 95% CIs for the treated versus not-treated groups. We categorized death-associated serious adverse events as neurologic versus non-neurologic events and performed multiple logistic regression analyses. We analyzed severe disability and mortality by outcomes of the mRS. Patient allocation was gathered by use of a poststudy survey. RESULTS: All-cause mortality trended in favor of treated patients (11.5% versus 16.1%; P = .079) and stroke-related mortality was significantly reduced in treated patients (7.5% versus 14.2%; P = .009). Logistic regression analysis for freedom from stroke-related mortality favored treatment (OR, 2.41; 95% CI, 1.22, 4.77; P = .012). Treated patients had numerically fewer neurologic causes of stroke-related deaths (52.9% versus 73.0%; P = .214). Among the 90-day survivors, nominally fewer treated patients were severely disabled (mRS 5) (5.6% versus 7.5%; OR, 1.72; 95% CI, 0.72, 4.14; P = .223). Differences in allocation of care did not account for the reduced mortality rates. CONCLUSIONS: There were consistent reductions in all-cause and stroke-related mortality in the NeuroFlo-treated patients. This reduction in mortality did not result in an increase in severe disability.

Does the cognitive measure Cog-4 show improvement among patients treated with thrombolysis after acute stroke?

BACKGROUND: Although the established measure of disability post stroke, the modified Rankin Scale emphasizes motor function and may underestimate the importance of cognitive impairment in more disabled patients. A subset of four items from the National Institutes of Health Stroke Scale has been proposed to assess cognitive function after stroke (Cog-4), and to correlate with modified Rankin Scale. Items correspond to orientation, executive function, language, and inattention. We investigated responsiveness of Cog-4 to treatment with thrombolysis and whether it offers information that supplements modified Rankin Scale. METHODS: We included 6268 patients from the Virtual International Stroke Trials Archive: 2734 received intravenous thrombolysis and 3534 were treated conservatively. We compared day 90 outcomes between treated and untreated groups, by modified Rankin Scale (illustrative) and by Cog-4 (primary measure) adjusting for age, baseline National Institutes of Health stroke scale, hemispheric lateralisation as well as baseline Cog-4 and baseline National Institutes of Health Stroke Scale excluding baseline Cog-4 separately. Analysis of Cog-4 was repeated within strata of 90 day modified Rankin Scale. Statistical analyses included proportional odds logistic regression and Cochran-Mantel-Haenszel test. RESULTS: Modified Rankin Scale showed a difference between treatment groups of expected magnitude (odds ratio 1·56; 95% confidence interval 1·43-1·72; P < 0·001). After adjustment for imbalance in baseline prognostic factors, the distribution of Cog-4 scores at 90 days was better in thrombolysed patients compared with nonthrombolysed patients (odds ratio 1·31; 95% confidence interval 1·18-1·47; P = 0·006). However, Cog-4 analysis stratified by 90-day modified Rankin Scale was neutral between treatment groups (OR 1·01; 95% CI 0·90-1·14), and Cog-4 was not responsive to treatment group even within modified Rankin Scale categories 4 and 5 despite substantial cognitive deficits in these patients. CONCLUSION: Although Cog-4 may be responsive to treatment effects, it does not provide additional information beyond modified Rankin Scale assessment.

Safety and feasibility of NeuroFlo use in eight- to 24-hour ischemic stroke patients.

BACKGROUND: Acute treatment of ischemic stroke patients presenting more than eight-hours after symptom onset remains limited and largely unproven. Partial aortic occlusion using the NeuroFlo catheter can augment cerebral perfusion in animals. We investigated the safety and feasibility of employing this novel catheter to treat ischemic stroke patients eight-hours to 24 h following symptom onset. METHODS: A multicenter, single-arm trial enrolled ischemic stroke patients at nine international academic medical centers. Eligibility included age 18-85 years old, National Institutes of Health stroke scale (NIHSS) score between four and 20, within eight-hours to 24 h after symptom onset, and perfusion-diffusion mismatch confirmed by magnetic resonance imaging. The primary outcome was all adverse events occurring from baseline to 30 days posttreatment. Secondary outcomes included stroke severity on neurological indices through 90 days. This study is registered with ClinicalTrials.gov, number NCT00436592. RESULTS: A total of 26 patients were enrolled. Of these, 25 received treatment (one excluded due to aortic morphology); five (20%) died. Favorable neurological outcome at 90 days (modified Rankin score 0-2 vs. 3-6) was associated with lower baseline NIHSS (P < 0·001) and with longer duration from symptom discovery to treatment. There were no symptomatic intracranial hemorrhages or parenchymal hematomas. Asymptomatic intracranial hemorrhage was visible on computed tomography in 32% and only on microbleed in another 20%. CONCLUSIONS: Partial aortic occlusion using the NeuroFlo catheter, a novel collateral therapeutic strategy, appears safe and feasible in stroke patients eight-hours to 24 h after symptom onset.

Introduction of portable computed tomography scanners, in the treatment of acute stroke patients via telemedicine in remote communities.

BACKGROUND: Thrombolysis is an established treatment in selected patients who present early to hospital after symptoms of acute ischaemic stroke. Treatment can only be offered after the patient has been assessed by highly trained physicians and imaging studies have ruled out a brain haemorrhage. This limits the wider availability of thrombolysis to patients in remote communities, especially in countries with limited resources. There has been considerable success with the use of TeleStroke to overcome such barriers. TeleStroke is feasible in remote hospitals provided there is an available computed tomography scanner, a fundamental prerequisite in the assessment of acute stroke and thrombolysis. This is a luxury not widely available, especially in remote sites. Recently, Neurologica introduced a portable computed tomography scanner that can be operated after minimal training. METHODS: We report our preliminary experience with the portable computed tomography scanner in a remote community where Telemedicine was successfully used to evaluate and treat patients presenting with symptoms suggestive of an acute ischaemic stroke. The University of Alberta Hospital in Edmonton, Canada was the 'hub' site and Wainwright Community Hospital was the 'spoke' site. RESULTS: Over a 3-month period, 18 patients were evaluated in the emergency department of the remote hospital where the referring physician felt that symptoms indicated potential for thrombolysis. All patients were evaluated remotely by a stroke neurologist in a TeleStroke service situated 207 km from the rural site. After clinical examination, cranial computed tomography scans were obtained with the portable scanner and evaluated by the stroke neurologist. In three patients, thrombolysis was not offered because the computed tomography showed evidence of brain haemorrhage: two intracerebral haemorrhage and one subarachnoid haemorrhage. Three patients meeting the standard criteria received thrombolysis within 4.5 h from onset of symptoms. There was a significant improvement in two patients. One patient did not make a good recovery. Repeat computed tomography scans showed a small haemorrhagic transformation in one patient. In the remaining 12 subjects, symptoms improved rapidly, were outside the window for thrombolysis, or were not consistent with an acute ischaemic stroke. INTERPRETATIONS: Our preliminary study shows that the portable scanner can be used successfully in the evaluation of patients in remote regions that are not within timely reach of stroke experts or do not have available conventional imaging with computed tomography scans. Telemedicine, in combination with the use of portable scanners, offers hope to a large remote population base that would otherwise not have access to appropriate acute stroke treatment.

New endpoint for ablation of ventricular tachycardia: change in QRS morphology with pacing at protected isthmus as index of isthmus block.

INTRODUCTION: Endpoints confirming block in the critical isthmus in sinus rhythm and with pace mapping have not been established. METHODS AND RESULTS: A 44-year-old man with a history of Tetralogy of Fallot presented with recurrent ventricular tachycardia (VT). Entrainment mapping was consistent with a macroreentrant circuit rotating in a clockwise fashion under the pulmonic valve. After termination of the VT in a critical isthmus located on the conal free wall, a pace map proximal to the site of successful ablation was consistent with a change in QRS morphology. This change in QRS morphology suggested critical isthmus block and successful ablation, which was confirmed by noninducibility with programmed stimulation. CONCLUSION: Evidence of conduction block can be used as an additional endpoint for successful ablation of VT.

Natural history of complications after intracerebral haemorrhage.

BACKGROUND AND PURPOSE: Numerous trials of haemostatic and neuroprotective agents for intracerebral haemorrhage (ICH) have failed. We characterized the risk of complications after ICH in a trial-eligible patient population, to inform safety in future trials. METHODS: We used the Virtual International Stroke Trials Archive database to identify placebo-treated patients with spontaneous ICH, who were not comatose at admission, where randomization took place within 4 h of symptom onset, and where serious complication and outcome data were available. We described the complications encountered and assessed whether the absence of common complications influenced attainment of good functional outcome (mRS < or =4) at 90 days using logistic regression. RESULTS: Of 201 patients examined, 70.2% experienced at least one serious complication. Neurological complications occurred in 21%, infections amongst 11%, and thromboembolic complications in 2%. Extension of the haemorrhage occurred most frequently: its absence was a significant predictor of good functional outcome (P < 0.0001, adjusted OR for good functional outcome = 21.9, 95% CI: [5.5, 88.3]). Neither infection, nor cardiac, nor thromboembolic complications influenced functional outcome at 90 days. CONCLUSIONS: Three month outcome in ICH patients depends on initial stroke severity and on enlargement of the haemorrhage. Our results should inform safety in future clinical trials of putative ICH therapies.