There is scant information available on the incidence of transient ischemic attack (TIA) in a defined population. This study defines incidence rates of first TIA and subtypes of TIA during 1985-1989 ...and compares the incidence to that obtained from a 1960-1972 cohort study.
Medical records of all residents of Rochester with potential diagnosis of TIA during 1985-1989 were screened to determine whether the case met the criteria for TIA. All available data were used to determine the vascular distribution of the TIA. Average annual age- and sex-adjusted incidence rates were calculated for 1985-1989, and results were compared with incidence rates determined in a Rochester-based 1960-1972 cohort study. RESILTS: Two hundred two cases of first TIA or amaurosis fugax occurred among Rochester residents during 1985-1989. The age- and sex-adjusted incidence rate for any TIA was 68/100 000 population. Incidence of amaurosis fugax was 13/100 000; anterior circulation (cerebral) TIA, 38/100 000; and vertebrobasilar distribution TIA, 14/100 000. Rates were similar to those determined from a 1960-1972 cohort study.
The incidence rate of TIA is 41% that of stroke incidence. TIA incidence in Rochester, Minn, is higher than has been previously reported for other sites throughout the world. Although comparison with prior time periods is difficult because of ascertainment issues, it appears that there has been no significant change in TIA incidence since the decade of the 1960s or earlier. This suggests that the most common mechanism for TIA (atherosclerosis) has not changed in prevalence, nor have risk factors leading to this mechanism.
The successful treatment of intracranial aneurysms is dependent on a full understanding of the anatomic relationship of a given aneurysm to its parent artery(s) and nearby branches. Furthermore, new ...endovascular technologies are often limited by size constraints. Currently, there is no complete atlas describing diameters for each major intracranial arterial segment. We sought to obtain these data by performing a systematic analysis of selected cerebral angiography images from the International Study of Unruptured Intracranial Aneurysms (ISUIA).
Four hundred and forty-five patients with unruptured intracranial aneurysms from the ISUIA database were reviewed. Using previously described techniques, artery diameters were measured for all arteries involved in the aneurysm neck for each patient.
Measurements were obtained from 695 different aneurysm-associated arterial segments among 445 patient angiograms (mean 1.6 measurements per aneurysm). Artery diameters, mean, median, SEM and IQRs based upon the different arterial segments are presented.
This angiographic almanac of aneurysm-associated intracranial arterial diameters may be of benefit in establishing standard norms through which devices, protocols and research aims may be developed.
Background Estimated glomerular filtration rate (eGFR) before coronary artery bypass graft (CABG) surgery is a key risk factor of in-hospital mortality. However, in patients with normal renal ...function before CABG, acute kidney injury develops after the procedure, making postoperative renal function assessment necessary for evaluation. Postoperative eGFR and its association with long-term survival have not been well studied. Methods We studied 13,593 consecutive CABG patients in northern New England from 2001 to 2006. Patients with preoperative dialysis were excluded. Data were linked to the Social Security Association Death Master File to assess long-term survival. Kaplan-Meier and log-rank techniques were used. Patients were stratified by established categories of postoperative eGFR (90 or greater, 60 to 89, 30 to 59, 15 to 29, and less than 15 mL · min−1 · 1.73 m−2 ). Results Median follow-up was 2.8 years (mean, 2.7; range, 0 to 5.5). Patients with moderate to severe acute kidney injury (less than 60) after CABG had significantly worse survival than patients with little or no acute kidney injury (90 or greater). Conclusions Patients having moderate to severe acute kidney injury after CABG surgery had worse 5-year survival compared with patients who had normal or near-normal renal function.
It has been widely recognized that mammal brain size predominantly increases over evolutionary time. Safi et al. Biol Lett 2005;1:283-286 questioned the generality of this trend, arguing that brain ...size evolution among bats involved reduction in multiple lineages as well as enlargement in others. Our study explored the direction of change in the evolution of bat brain size by estimating brain volume in fossil bats, using synchrotron radiation X-ray tomographic microscopy. Virtual endocasts were generated from 2 Hipposideros species: 3 specimens of Oligocene Hipposideros schlosseri (∼35 Ma) and 3 of Miocene Hipposideros bouziguensis (∼20 Ma). Upper molar tooth dimensions (M(2) length × width) collected for 43 extant insectivorous bat species were used to derive empirical formulae to estimate body mass in the fossil bats. Brain size was found to be relatively smaller in the fossil bats than in the average extant bat both with raw data and after allowing for phylogenetic inertia. Phylogenetic modeling of ancestral relative brain size with and without fossil bats confirmed a general trend towards evolutionary increase in this bat lineage.
GPR120 agonists have therapeutic potential for the treatment of diabetes, but few selective agonists have been reported. We identified an indazole-6-phenylcyclopropylcarboxylic acid series of GPR120 ...agonists and conducted SAR studies to optimize GPR120 potency. Furthermore, we identified a (S,S)-cyclopropylcarboxylic acid structural motif which gave selectivity against GPR40. Good oral exposure was obtained with some compounds displaying unexpected high CNS penetration. Increased MDCK efflux was utilized to identify compounds such as 33 with lower CNS penetration, and activity in oral glucose tolerance studies was demonstrated. Differential activity was observed in GPR120 null and wild-type mice indicating that this effect operates through a mechanism involving GPR120 agonism.
Current rabbit stroke models often depend on symptoms as endpoints for embolization and produce wide variation in location, size, and severity of strokes. In a further refinement of an angiographic ...embolic stroke model, localized infarctions were correlated to neurologic deficits with the goal to create a rabbit model for long-term studies of therapies after stroke.
New Zealand White rabbits (4-5 kg; N = 71) had selective internal carotid artery (ICA) angiography and a single clot was injected. At 24 hours, neurologic assessment score (NAS) was measured on an 11-point scale (0, normal; 10, dead). Brains were removed and stained to identify stroke areas. All animals with single strokes (n = 31) were analyzed by specific brain structure involvement, and NAS values were correlated.
Stroke incidence differed by location, with cortex, subcortical, and basal ganglia regions highest. The middle cerebral artery (MCA), at 52%, and anterior cerebral artery (ACA), at 29%, were most commonly involved, with the largest stroke volumes in the ACA distribution. Brainstem and cerebellum strokes had disproportionately severe neurologic deficits, scoring 2.25 +/- 1.0 on the NAS, which represented a significant (P < .02) difference versus cortex (0.5 +/- 0.2), subcortical (1.3 +/- 0.4), and basal ganglia (0.5 +/- 0.3), all in the frontal or parietal regions.
MCA and ACA distributions included 81% of strokes. These sites were relatively silent (potentially allowing longer-term survival studies) whereas others in the posterior circulation produced disproportionately severe symptoms. Symptoms were not reliable indicators of stroke occurrence, and other endpoints such as imaging may be required. These are important steps toward refinement of the rabbit stroke model.
Objective We sought to examine the relationship of the QTc interval with mortality and functional outcome after acute ischemic stroke, and determine whether a threshold cutoff is present beyond which ...risk of death increases. Methods The QTc interval was measured for all patients presenting to the emergency department. The outcomes were mortality at 90 days and functional outcome at hospital discharge. The cutoffs were determined plotting martingale residuals. Results Patients with a prolonged QTc interval were more likely to die within 90 days compared with patients without a prolonged interval (relative risk RR 2.5; 95% confidence interval CI 1.5-4.1; P < .001). The estimated survival at 90 days was 70.5% and 87.1%, respectively. This association retained statistical significance after adjusting for age and National Institutes of Health Stroke Scale score (RR 1.7; 95% CI 1.0-2.9; P = .043). Patients with a prolonged QTc interval were also more likely to have poor functional status compared with patients without a prolonged interval (odds ratio 1.8; 95% CI 1.2-3.0; P = .006). This association was not statistically significant after adjusting for age and National Institutes of Health Stroke Scale score (odds ratio 1.2; 95% CI 0.7-2.4). The identified threshold cutoffs for increased risk of death at 90 days were 440 milliseconds for women and 438 milliseconds for men. Conclusion There appears to be an increased risk of early death in patients with acute ischemic stroke and a prolonged QTc interval at the time of emergency department presentation. Prognosis appears to be worse with QTc intervals longer than 440 milliseconds in women and longer than 438 milliseconds in men.
ABSTRACT
BACKGROUND
School administrators and teachers face difficult decisions about how best to use school resources to meet academic achievement goals. Many are hesitant to adopt prevention ...curricula that are not focused directly on academic achievement. Yet, some have hypothesized that prevention curricula can remove barriers to learning and, thus, promote achievement. We examined relationships among school levels of student substance use and risk and protective factors that predict adolescent problem behaviors and achievement test performance.
METHODS
Hierarchical generalized linear models were used to predict associations involving school‐averaged levels of substance use and risk and protective factors and students' likelihood of meeting achievement test standards on the Washington Assessment of Student Learning, statistically controlling for demographic and economic factors known to be associated with achievement.
RESULTS
Levels of substance use and risk/protective factors predicted the academic test score performance of students. Many of these effects remained significant even after controlling for model covariates.
CONCLUSIONS
Implementing prevention programs that target empirically identified risk and protective factors has the potential to have a favorable effect on students' academic achievement.
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