The protective effect of daytime sleep on planning and risk-related decision-making in emerging adults.

We assessed the effect of a daytime sleep opportunity on planning and risk-related decision-making in emerging adults using multiple neurobehavioral assessments. A total of 136 healthy emerging adults (20.0 ± 1.5 years), 65% female, performed the Risky-Gains Task and the Tower of London test twice. Between these assessments, they were randomized to either have a sleep opportunity monitored by polysomnography (Sleep group, n = 101) or to stay awake (Wake group, n = 35). During Test 2, in comparison to the Sleep group, the Wake group showed increased sleepiness, worse planning ability and more decrease in reaction times when selecting risky choices. Changes in Tower of London test steps used and Risky-Gains Task response time correlated with the number of central and frontal fast sleep spindles, respectively. These results indicate that among emerging adults who commonly have poor sleep patterns, a daytime sleep opportunity was related to better planning ability, better psychomotor vigilance and stable response speeds in risk-related decision-making. Changes in planning and risk-related decision-making correlated with the number of sleep spindles during the nap, supporting a specific role for sleep in modulating planning and potentially other higher-order cognitive functions.

Current status of intravenous thrombolysis for acute ischemic stroke in Asia.

BACKGROUND: Data regarding thrombolysis for acute ischemic stroke in Asia are scarce and only a small percentage of patients are thrombolysed. The dose of intravenous tissue plasminogen activator (IV-tPA) in Asia remains controversial. Case-controlled observation studies in Asia included only Japanese patients and suggested the clinical efficacy and safety of low-dose IV-tPA (0.6 mg/kg body weight; max 60 mg) comparable to standard dose (0.9 mg/kg body weight; max. 90 mg). Reduced treatment cost, lower symptomatic intracerebral hemorrhage risk and comparable efficacy encouraged many Asian centers to adopt low-dose or even variable-dose IV-tPA regimens. We evaluated various Asian thrombolysis studies and compared with SITS-MOST registry and NINDS trial. METHODS: We included the published studies on acute ischemic stroke thrombolysis in Asia. Unadjusted relative risks and 95% Confidence intervals were calculated for each study. Pooled estimates from random effects models were used because the tests for heterogeneity were significant. RESULTS: We found only 18 publications regarding acute ischemic stroke thrombolysis in Asia that included total of 9300 patients. Owing to ethnic differences, stroke severity, small number of cases in individual reports, outcome measures and tPA dose regimes, it is difficult to compare these studies. Functional outcomes were almost similar (to Japanese studies) when lower-dose IV-tPA was used in non-Japanese populations across Asia. Interestingly, with standard dose IV-tPA, considerably better functional outcomes were observed, without increasing symptomatic intracerebral hemorrhage rates. CONCLUSIONS: Variable dose regimens of IV-tPA are used across Asia without any reliable or established evidence. Establishing a uniform IV-tPA regimen is essential since the rapid improvements in health-care facilities and public awareness are expected to increase the rates of thrombolysis in Asia.

Embolic Doppler ultrasound signal detection using continuous wavelet transform to detect multiple vascular emboli.

BACKGROUND: Ischemic stroke is mainly caused by embolism. Vascular emboli can be solid or gaseous and can be non-invasively registered by transcranial Doppler ultrasound as microembolic signals (MESs). The existing methods are limited as they do not distinguish between cases in which a single embolus is present and those in which multiple emboli -- perhaps a mix of those gaseous and solid in nature -- are present. In a previous in vitro study, we have developed a wavelet-based algorithm to detect multiple emboli. We proceed with this technique to investigate whether it could prove useful in patients. METHOD: MESs were collected during emboli monitoring from patients undergoing carotid artery stenting and from patients having middle cerebral artery stenosis, and continuous wavelet transform was used to detect multiple emboli. RESULTS: From 17 MESs recorded from middle cerebral artery stenosis patients, we found no multiple MES. From 306 MESs recorded from carotid stenting, we found 31 multiple MESs. CONCLUSION: Multiple emboli were detected and quantified in patients using continuous wavelet transform. These were difficult to observe using conventional analysis techniques.

Complication of acute stroke: A study in ten Asian countries

Background and Objective: There is a paucity of studies looking into the frequency of complications after stroke among Asians. We sought to determine the frequency and rate of complications among Asians after acute stroke. Methods: Consecutive patients with acute stroke among 10 participating Asian countries were included in the study. The frequency and timing of pre-determined complications, and their relation to area of admission were noted. Results: Of the 1,153 patients included in the study, 423 (41.9%) developed complications within the first 2 weeks of stroke. Recurrent stroke, chest infections and urinary tract infections were most commonly encountered, and were most frequent within the first week of stroke onset. A lower rate of complications was noted among patients admitted at an organized stroke unit. Conclusion: There is a similar rate of frequency and timing of complications after acute stroke among Asians as compared with other populations.