How predictors and patterns of stroke recurrence after a TIA differ during the first year of follow-up

The highest risk of subsequent stroke after a TIA occurs within the first week after the index event. However, the risk of stroke recurrence (SR) remains high during the first year of follow-up. We studied the temporal pattern and predictors of SR (at 7 days and from 7 days to 1-year follow-up). Between April 2008 and December 2009, we included 1,255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We determined the short-term (at 7 days) and long-term (from 8 days to 1 year) risk of SR. Patients who underwent short-term recurrence and long-term recurrence were compared with regard to clinical findings, vascular territories, and etiology. Enough information (clinical variables and extracranial vascular imaging) was assessed in 1,137 (90.6 %) patients. The 7-day stroke risk was 2.6 %. 32 (3.0 %) patients had an SR after 7-day follow-up. Multiple TIA (HR 3.50, 1.67-7.35, p = 0.001) and large artery atherosclerosis (HR 2.51, 1.17-5.37, p = 0.018) were independent predictors of early SR, whereas previous stroke (HR 1.40, 1.03-1.92, p = 0.034) and coronary heart disease (2.65, 1.28-5.50, p = 0.009) were independent predictors of late SR. Notoriously, 80 % of SR happened in the same territory of the index TIA at 7-day follow-up, whereas only 38 % during the long-term follow-up (p < 0.001). Different predictors of SR were identified throughout the follow-up period. Moreover, the ischemic mechanism differed in early and late stroke recurrences.

Emergence of acoustic and optical bands in elastic systems

Two elastic systems are considered in this work: A special linear chain of harmonic oscillators and a quasi one-dimensional vibrating rod. Starting in both cases with a locally periodic system formed by unit cells with a single element, these cells are converted into binary cells. The acoustic and optical bands then appear. For the vibrating rod experimental values are compared with theoretical results; in particular, the normal-mode amplitudes are obtained and the agreement is excellent.

Primary intraocular chondrosarcoma in a dog

A five-year-old male Cocker Spaniel was presented for evaluation of the right eye due to discomfort, abundant purulent discharge and progressive enlargement of the eyeball. The owner revealed that the right eye has appeared to be inflamed and smaller then the left eye for years. Ophthalmic examination revealed corneal perforation, buphthalmia and conjuctival hyperemia. Enucleating was performed due to signs of endophthalmitis and ocular discomfort. Histopathology revealed a multilobulated proliferation of chondrocytes producing hyaline cartilage with occasional pleomorphism and binucleate cells. A diagnosis of primary intraocular chondrosarcoma was done.

Effect of L-valine supplementation to a wheat-based diet with leucine excess on performance, gene expression, and serum concentration of amino acids

Excess Leu in the diet reduces the expression of the cationic AA transporter b(0,+), absorption of Lys and Arg, feed intake, and ADG of pigs. Because Val competes with Leu for absorption, surplus Val may correct some of these effects. An experiment was conducted to analyze the effect of surplus Val in a basal wheat (Triticum aestivum) diet fortified with free Lys, Thr, and Met and containing excess Leu and Ile on performance, expression of genes encoding b(0,+), and serum concentrations of AA. Sixteen pigs (30.3 ± 2.1 kg BW) were used. Treatments were wheat based with excess Leu and Ile (T1) and T1 plus 0.44% L-Val (T2). At the end of the 21-d study, 12 pigs were euthanized; jugular blood was collected to analyze serum AA and jejunal mucosa to measure expression of b(0,+). Surplus Val increased (P < 0.05) ADG and G:F and serum Val, Lys, and Arg but did not affect (P > 0.10) b(0,+) expression. Although analyzed Val content in the basal diet was lower than calculated, the increased serum Lys and improved pig performance may suggest that excess Leu limits Val availability and that surplus Val could correct some of the negative effects of excess Leu.

Clinical management guidelines for subarachnoid haemorrhage. Diagnosis and treatment

OBJECTIVE

To update the Spanish Society of Neurology's guidelines for subarachnoid haemorrhage diagnosis and treatment.

MATERIAL AND METHODS

A review and analysis of the existing literature. Recommendations are given based on the level of evidence for each study reviewed.

RESULTS

The most common cause of spontaneous subarachnoid haemorrhage (SAH) is cerebral aneurysm rupture. Its estimated incidence in Spain is 9/100 000 inhabitants/year with a relative frequency of approximately 5% of all strokes. Hypertension and smoking are the main risk factors. Stroke patients require treatment in a specialised centre. Admission to a stroke unit should be considered for SAH patients whose initial clinical condition is good (Grades I or II on the Hunt and Hess scale). We recommend early exclusion of aneurysms from the circulation. The diagnostic study of choice for SAH is brain CT (computed tomography) without contrast. If the test is negative and SAH is still suspected, a lumbar puncture should then be performed. The diagnostic tests recommended in order to determine the source of the haemorrhage are MRI (magnetic resonance imaging) and angiography. Doppler ultrasonography studies are very useful for diagnosing and monitoring vasospasm. Nimodipine is recommended for preventing delayed cerebral ischaemia. Blood pressure treatment and neurovascular intervention may be considered in treating refractory vasospasm.

CONCLUSIONS

SAH is a severe and complex disease which must be managed in specialised centres by professionals with ample experience in relevant diagnostic and therapeutic processes.

Efficacy and safety of liposomal cytarabine in children with primary CNS tumours with leptomeningeal involvement

PURPOSE

To assess the efficacy and safety of liposomal cytarabine in the treatment of de novo and relapsed leptomeningeal involvement in children with primary CNS tumours.

METHODS

Data from clinical charts were entered into a database for consecutive unselected patients (n=20) from nine Spanish centres. Diagnosis of leptomeningeal involvement was confirmed by cytology, MRI and/or CT scan. The dose of liposomal cytarabine used varied from 20 to 50 mg, by age.

RESULTS

There were 8 females and 12 males, mean age 7.3 years (range 8 months to 18 years). The tumours were: 10 medulloblastomas, 4 ependymomas, 3 primitive neuroectodermal tumours and 3 other tumours. Fourteen had undergone previous chemotherapy and 12 radiotherapy. Nine received concurrent chemotherapy and 2 concurrent radiotherapy. Median follow-up was 244.5 days (range 12- 869). Patients received a median of 5 doses (range 1-9) of liposomal cytarabine. A neurological response (complete or partial) was seen in 11/19 (58%) and a cytological response in 7/10 (64%). Median time to neurological progression exceeded 180 days (range 12-869). Adverse effects were reported in 11/20 patients, but none was grade IV.

DISCUSSION

Liposomal cytarabine was well tolerated and efficacious in this patient group, but prospective randomised trials are needed.

Unconjugated hyperbilirubinemia is inversely associated with non-alcoholic steatohepatitis (NASH)

BACKGROUND

It has been recognised that unconjugated bilirubin contains hepatic anti-fibrogenic and anti-inflammatory properties and is a potent physiological antioxidant cytoprotectant. We believe that unconjugated hyperbilirubinemia may protect against development of non-alcoholic steatohepatitis (NASH).

AIM

This study was conducted to assess the association of serum unconjugated bilirubin levels and histological liver damage in non-alcoholic fatty liver disease (NAFLD).

METHODS

This was a retrospective analysis involving adult patients from a tertiary medical centre undergoing liver biopsy to evaluate suspected NAFLD or NASH and a control group without NAFLD based on normal liver ultrasound, labs and history. Identification of unconjugated hyperbilirubinemia was based on the presence of predominantly unconjugated bilirubin ≥1.0 mg/dL (17.1 μmol/L) while fasting, in the absence of haemolytic disease or other hepatic function alteration.

RESULTS

Six-hundred and forty-one patients were included. Unconjugated hyperbilirubinemia was inversely associated with NASH (OR 16.1, 95% CI 3.7-70.8 P < 0.001). Of the patients without NAFLD (133 patients), 13 (9.8%) had unconjugated hyperbilirubinemia (range 1.0-1.8, mean 1.4). Of the patients with NAFLD without NASH (285 patients), 32 (11.2%) had unconjugated hyperbilirubinemia (range 1.0-3.0, mean 1.4). Of the patients with NASH (223 patients), three (1.3%) had unconjugated hyperbilirubinemia (1.0, 1.1, 1.4).

CONCLUSIONS

Unconjugated hyperbilirubinemia is inversely associated with the histopathological severity of liver damage in non-alcoholic fatty liver disease.

Contribution of ion binding affinity to ion selectivity and permeation in KcsA, a model potassium channel

Ion permeation and selectivity, key features in ion channel function, are believed to arise from a complex ensemble of energetic and kinetic variables. Here we evaluate the contribution of pore cation binding to ion permeation and selectivity features of KcsA, a model potassium channel. For this, we used E71A and M96V KcsA mutants in which the equilibrium between conductive and nonconductive conformations of the channel is differently shifted. E71A KcsA is a noninactivating channel mutant. Binding of K(+) to this mutant reveals a single set of low-affinity K(+) binding sites, similar to that seen in the binding of K(+) to wild-type KcsA that produces a conductive, low-affinity complex. This seems consistent with the observed K(+) permeation in E71A. Nonetheless, the E71A mutant retains K(+) selectivity, which cannot be explained on the basis of just its low affinity for this ion. At variance, M96V KcsA is a rapidly inactivating mutant that has lost selectivity for K(+) and also conducts Na(+). Here, low-affinity binding and high-affinity binding of both cations are detected, seemingly in agreement with both being permeating species in this mutant channel. In conclusion, binding of the ion to the channel protein seemingly explains certain gating, ion selectivity, and permeation properties. Ion binding stabilizes greatly the channel and, depending upon ion type and concentration, leads to different conformations and ion binding affinities. High-affinity states guarantee binding of specific ions and mediate ion selectivity but are nonconductive. Conversely, low-affinity states would not discriminate well among different ions but allow permeation to occur.

Hemorrhage/contrast staining areas after mechanical intra-arterial thrombectomy in acute ischemic stroke: imaging findings and clinical significance

BACKGROUND AND PURPOSE

The aim of this study was to report the CT evolution and clinical significance of HCA after intra-arterial mechanical thrombectomy (revascularization by using retrievers and/or other mechanical devices without concomitant delivery of intra-arterial thrombolytics) in our patients. These lesions are common after intra-arterial thrombolysis, being considered a negative prognostic sign. Their significance after pure mechanical thrombectomy remains unknown.

MATERIALS AND METHODS

Forty-eight patients were treated with mechanical thrombectomy by using retrievable stents between April 2010 and February 2011. All patients underwent initial (first 24 hours) and follow-up (48-72 hours) nonenhanced CT. We retrospectively analyzed the clinical and radiologic data of the patients with HCA and compared them with controls.

RESULTS

Fifteen of 48 patients presented with HCA. The site of occlusion was the MCA in 7 patients, both the extra- and intracranial segments of the ICA in 6, and the intracranial ICA in 2. In 7 patients, previous intravenous thrombolysis was administered. Complete recanalization (TICI 3) was achieved in 12 patients, and incomplete recanalization (TICI 2b), in 3. The location of HCA was the subarachnoid space in 6 patients, the brain parenchyma in 4 patients, and both in 5 patients. The HCA were asymptomatic in all patients. There was no statistical difference in final NIHSS score reduction (NIHSS pretreatment-NIHSS at discharge) between patients and controls.

CONCLUSIONS

In our series, HCA are common after mechanical thrombectomy but do not carry an increased risk of symptomatic hemorrhage or negative prognosis. These data might be related to the high rate of recanalization and the absence of intra-arterial thrombolytics.

Analysing the effect of public health campaigns on reducing excess weight: a modelling approach for the Spanish Autonomous Region of the Community of Valencia

Excess weight is fast becoming a serious health concern in the developed and developing world. The concern of the public health sector has lead to the development of public health campaigns, focusing on two-fold goals: to inform the public as to the health risks inherent in being overweight, and the benefits of a change in nutritional behaviour. Recent studies indicate that the effects of the average public health campaign on the target community is around 5%. In this study we aim to quantify the effect of different public health campaigns on lifestyle behaviour in the target populations in order to bring about weightloss in a significant number of people over the next few years. This study is based on recent works that consider excess weight as a consequence of the transmission of unhealthy lifestyles from one individual to another. Following this point of view, first a mathematical model is presented. Then, policies based on public health campaigns addressed to stop people gaining weight (prevention; this type of policy acts on individuals in order to maintain their weight and to stop an increase in weight) and, policies addressed to overweight individuals to reduce their weight (treatment; these campaigns act on overweight and/or obese individuals in order to reduce their weight) are simulated in order to evaluate their effectiveness. The study concludes that combination of preventive plus treatment campaigns are more effective than considering them separately.

Effect of excess levels of lysine and leucine in wheat-based, amino acid-fortified diets on the mRNA expression of two selected cationic amino acid transporters in pigs

An experiment was conducted to evaluate the effect of excess levels of Leu and Lys on the expression of b(0,+) and CAT-1 mRNA in jejunum, liver and the muscles Longissimus dorsi (LDM) and Semitendinosus (STM). Twenty pigs with an average initial BW of 16.4 ± 1.7 kg were used in a Randomized Complete Block. Dietary treatments (T) were as follows: T1, basal diet; T2, basal plus 3.5 g l-Lys/kg diet; T3, basal plus 1.5 g l-Leu/kg diet; T4, basal plus 3.5 g l-Lys plus 1.5 g l-Leu/kg diet. Diets in T1 and T3 met 100% the requirement of Lys for pigs within the 10 to 20 kg body weight range; diets in T2 and T4 contained 35% excess of Lys. Also, diets in T1 and T2 supplied 104%, whereas diets in T3 and T4 supplied 116% the requirement of Leu. The expression of b(0,+) in jejunum was reduced (p = 0.002) because of the supplementation of l-Leu, but l-Lys supplementation had no effect (p = 0.738). In contrast, the expression of b(0,+) in STM (p = 0.012) and liver (p = 0.095) was reduced by the high level of Lys, but Leu had no effect (p > 0.100). CAT-1 expression in STM increased by high Lys (p = 0.023) and Leu (p = 0.007) levels. In liver, the expression of CAT-1 substantially increased (p = 0.001) because of Lys. In conclusion, excess levels of dietary Lys and Leu affect the expression of cationic amino acid transporters, and this effect varies depending on the studied tissue.