The risk of stroke within a week of minor stroke or transient ischemic attack

Background: The risk of stroke is highest in the first week following an index stroke or transient ischemic attack (TIA). Recent evidence indicates that prompt pharmacological treatment and evaluation may help mitigate this risk. Objective: To identify risk factors for recurrent stroke 1 week after index cerebrovascular event and review evidence for early and aggressive evaluation and management. Methods: We searched the National Library of Medicine Pubmed database to identify studies reporting recurrent or secondary stroke in individuals with identified stroke or TIA. Results/conclusion: The risk of recurrent stroke in the week after a TIA or minor stroke is up to 10%. Factors identified with risk of early stroke recurrence include age, elevated blood pressure, clinical symptoms of motor weakness or speech disturbance, and large vessel atherothrombotic mechanism. Studies have shown that timely initiation of stroke preventative therapy may reduce the risk of stroke within this early period.     

Non-invasive prediction of development of hepatocellular carcinoma using transient elastography in patients with chronic liver disease

Prognosis of patients with chronic liver disease is determined by the extent and progression of liver fibrosis, which may ultimately lead to hepatocellular carcinoma (HCC). Liver biopsy (LB) is regarded as the gold standard to estimate the extent of liver fibrosis. However, because LB has several limitations, the foremost being its invasiveness, several non-invasive methods for assessing liver fibrosis have been proposed. Of these, transient elastography (TE) provides an accurate representation of the extent of liver fibrosis. Furthermore, recent studies have focused on the usefulness of TE for assessing the risk of HCC development and HCC recurrence after curative treatment, and developed novel models to calculate the risk of HCC development based on TE findings. These issues are discussed in this expert review.     

Capturing fleeting intermediates in a catalytic C–H amination reaction cycle

We have applied an ambient ionization technique, desorption electrospray ionization MS, to identify transient reactive species of an archetypal C–H amination reaction catalyzed by a dirhodium tetracarboxylate complex. Using this analytical method, we have detected previously proposed short-lived reaction intermediates, including two nitrenoid complexes that differ in oxidation state. Our findings suggest that an Rh-nitrene oxidant can react with hydrocarbon substrates through a hydrogen atom abstraction pathway and raise the intriguing possibility that two catalytic C–H amination pathways may be operative in a typical bulk solution reaction. As highlighted by these results, desorption electrospray ionization MS should have broad applicability for the mechanistic study of catalytic processes.     

Atorvastatin Reduces First and Subsequent Vascular Events Across Vascular Territories: The SPARCL Trial

BackgroundIn the SPARCL (Stroke Prevention by Aggressive Reduction in Cholesterol Levels) trial, atorvastatin was compared with placebo in 4,731 participants with recent stroke or transient ischemic attack and no known coronary heart disease. Atorvastatin reduced the first occurrence of stroke and the first occurrence of a composite of vascular events.ObjectivesThe aim of this post hoc analysis was to assess the occurrence of all (first and subsequent) vascular events and the effect of atorvastatin to reduce these events by vascular territory (cerebrovascular, coronary, or peripheral) in SPARCL.MethodsTreatment effects on total adjudicated vascular events, overall and by vascular territory, were summarized by marginal proportional hazards models. Vascular event rates were estimated for each treatment group with cumulative incidence functions.ResultsThe placebo group had an estimated 41.2 first and 62.7 total vascular events per 100 participants over 6 years. There were 164 fewer first and 390 fewer total vascular events in the atorvastatin group (total events hazard ratio: 0.68; 95% confidence interval: 0.60 to 0.77). The total events reduction included 177 fewer cerebrovascular, 170 fewer coronary, and 43 fewer peripheral events. Over 6 years, an estimated 20 vascular events per 100 participants were avoided with atorvastatin treatment.ConclusionsIn participants with recent stroke or transient ischemic attack, the total number of vascular events prevented with atorvastatin was more than twice the number of first events prevented. Total event reduction provides a comprehensive metric to capture the totality of atorvastatin clinical efficacy in reducing disease burden after stroke or transient ischemic attack. (Lipitor in the Prevention of Stroke, for Patients Who Have Had a Previous Stroke [SPARCL]; NCT00147602)