We recently identified the thalamic dopaminergic system in the human and macaque monkey brains, and, based on earlier reports on the paucity of dopamine in the rat thalamus, hypothesized that this dopaminergic system was particularly developed in primates. Here we test this hypothesis using immunohistochemistry against the dopamine transporter (DAT) in adult macaque and rat brains. The extent and density of DAT-immunoreactive (-ir) axons were remarkably greater in the macaque dorsal thalamus, where the mediodorsal association nucleus and the ventral motor nuclei held the densest immunolabeling. In contrast, sparse DAT immunolabeling was present in the rat dorsal thalamus; it was mainly located in the mediodorsal, paraventricular, ventral medial, and ventral lateral nuclei. The reticular nucleus, zona incerta, and lateral habenular nucleus held numerous DAT-ir axons in both species. Ultrastructural analysis in the macaque mediodorsal nucleus revealed that thalamic interneurons are a main postsynaptic target of DAT-ir axons; this suggests that the marked expansion of the dopamine innervation in the primate in comparison to the rodent thalamus may be related to the presence of a sizable interneuron population in primates. We remark that it is important to be aware of brain species differences when using animal models of human brain disease.

Background and Purpose-Although experimental data suggest that statin therapy may improve neurological outcome after acute cerebral ischemia, the results from clinical studies are conflicting. We performed a systematic review and meta-analysis investigating the relationship between statin therapy and outcome after ischemic stroke. Methods-The primary analysis investigated statin therapy at stroke onset (prestroke statin use) and good functional outcome (modified Rankin score 0 to 2) and death. Secondary analyses included the following: (1) acute poststroke statin therapy (≤72 hours after stroke), and (2) thrombolysis-treated patients. Results-The primary analysis included 113 148 subjects (27 studies). Among observational studies, statin treatment at stroke onset was associated with good functional outcome at 90 days (pooled odds ratio [OR], 1.41; 95% confidence interval [CI], 1.29-1.56; P<0.001), but not 1 year (OR, 1.12; 95% CI, 0.9-1.4; P=0.31), and with reduced fatality at 90 days (pooled OR, 0.71; 95% CI, 0.62-0.82; P<0.001) and 1 year (OR, 0.80; 95% CI, P=0.01). In the single randomized controlled trial reporting 90-day functional outcome, statin treatment was associated with good outcome (OR, 1.5; 95% CI, 1.0-2.24; P=0.05). No reduction in fatality was observed on meta-analysis of data from 3 randomized controlled trials (P=0.9). In studies restricted to of thrombolysis-treated patients, an association between statins and increased fatality at 90 days was observed (pooled OR, 1.25; 95% CI, 1.02-1.52; P=0.03, 3 studies, 4339 patients). However, this association was no longer present after adjusting for age and stroke severity in the largest study (adjusted OR, 1.14; 95% CI, 0.90-1.44; 4012 patients). Conclusion-In the largest meta-analysis to date, statin therapy at stroke onset was associated with improved outcome, a finding not observed in studies restricted to thrombolysis-treated patients. 5-12 Experimental and clinical data also provide some evidence that statins may have neuroprotective effects after acute cerebral ischemia. [7][8][9][10][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] In animal models, treatment with statins either before, or early after, cerebral arterial occlusion has been associated with reduced infarct volume and improved neurological function. [5][6][7][8][9][10]13,14 Data are conflicting regarding the relationship between acute statin therapy and outcome after human ischemic stroke. Some authors have reported improved survival and functional outcome associated with statin treatment, but these findings have not been consistently replicated. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][31][32][33][34][35][36] Interpretations can be difficult because of limited sample sizes in some reports and possible bias in statin allocation in other studies, particularly those in which statins were allocated in a nonrandomized fashion. Some authors have also reported worse outcomes in patients treated with the combination of acute statins and intravenous thro...

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Background: Several clinical scales have been developed for predicting stroke recurrence. These clinical scores could be extremely useful to guide triage decisions. Our goal was to compare the very early predictive accuracy of the most relevant clinical scores [age, blood pressure, clinical features and duration of symptoms (ABCD) score, ABCD and diabetes (ABCD2) score, ABCD and brain infarction on imaging score, ABCD2 and brain infarction on imaging score, ABCD and prior TIA within 1 week of the index event (ABCD3) score, California Risk Score, Essen Stroke Risk Score and Stroke Prognosis Instrument II] in consecutive transient ischemic attack (TIA) patients. Methods: Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). A neurologist treated all patients within the first 48 h after symptom onset. The duration and typology of clinical symptoms, vascular risk factors and etiological work-ups were prospectively recorded in a case report form in order to calculate established prognostic scores. We determined the early short-term risk of stroke (at 7 and 90 days). To evaluate the performance of each model, we calculated the area under the receiver operating characteristic curve. Cox proportional hazards multivariate analyses determining independent predictors of stroke recurrence using the different components of all clinical scores were calculated. Results: We calculated clinical scales for 1,137 patients (90.6%). Seven-day and 90-day stroke risks were 2.6 and 3.8%, respectively. Large-artery atherosclerosis (LAA) was observed in 190 patients (16.7%). We could confirm the predictive value of the ABCD3 score for stroke recurrence at the 7-day follow-up [0.66, 95% confidence interval (CI) 0.54–0.77] and 90-day follow-up (0.61, 95% CI 0.52–0.70), which improved when we added vascular imaging information and derived ABCD3V scores by assigning 2 points for at least 50% symptomatic stenosis on carotid or intracranial imaging (0.69, 95% CI 0.57–0.81, and 0.63, 95% CI 0.51–0.69, respectively). When we evaluated each component of all clinical scores using Cox regression analyses, we observed that prior TIA and LAA were independent predictors of stroke recurrence at the 7-day follow-up [hazard ratio (HR) 3.97, 95% CI 1.91–8.26, p < 0.001, and HR 3.11, 95% CI 1.47–6.58, p = 0.003, respectively] and 90-day follow-up (HR 2.35, 95% CI 1.28–4.31, p = 0.006, and HR 2.20, 95% CI 1.15–4.21, p = 0.018, respectively). Conclusion: All published scores that do not take into account vascular imaging or prior TIA when identifying stroke risk after TIA failed to predict risk when applied by neurologists. Clinical scores were not able to replace extensive emergent diagnostic evaluations such as vascular imaging, and they should take into account unstable patients with recent prior transient episodes.

However, the complexity of this technique justifies the development of collaborative stroke center networks with interhospital transfers of eligible patients. 6 To date, these stroke care networks have been implemented in regional settings, connecting a comprehensive stroke center (CSC) with primary stroke centers and general hospitals. 6 This approach has been designed principally to improve the rates of IVT in IS, but it has also played an important role in patients eligible Background and Purpose-The complexity of endovascular revascularization treatment (ERT) in acute ischemic stroke and the small number of patients eligible for treatment justify the development of stroke center networks with interhospital patient transfers. However, this approach might result in futile transfers (ie, the transfer of patients who ultimately do not undergo ERT). Our aim was to analyze the frequency of these futile transfers and the reasons for discarding ERT and to identify the possible associated factors. Methods-We analyzed an observational prospective ERT registry from a stroke collaboration ERT network consisting of 3 hospitals. There were interhospital transfers from the first attending hospital to the on-call ERT center for the patients for whom this therapy was indicated, either primarily or after intravenous thrombolysis (drip and shift). Results-The ERT protocol was activated for 199 patients, 129 of whom underwent ERT (64.8%). A total of 120 (60.3%) patients required a hospital transfer, 50 of whom (41%) ultimately did not undergo ERT. There were no differences in their baseline characteristics, the times from stroke onset, or in the delays in interhospital transfers between the transferred patients who were treated and those who were not treated. The main reasons for rejecting ERT after the interhospital transfer were clinical improvement/arterial recanalization (48%) and neuroimaging criteria (32%). Conclusions-Forty-one percent of the ERT transfers were futile, but none of the baseline patient characteristics predicted this result. Futility could be reduced if repetition of unnecessary diagnostic tests was avoided.