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Joaquín Serena

Publications and source records attributed to Joaquín Serena.

At least 19 recordsLinked to original sources
PubMed2007

Ischemic preconditioning reveals that GLT1/EAAT2 glutamate transporter is a novel PPARgamma target gene involved in neuroprotection.

Excessive levels of extracellular glutamate in the nervous system are excitotoxic and lead to neuronal death. Glutamate transport, mainly by glutamate transporter GLT1/EAAT2, is the only mechanism for maintaining extracellular glutamate concentrations below excitotoxic levels in the central nervous system. We recently showed that neuroprotection after experimental ischemic preconditioning (IPC) involves, at least partly, the upregulation of the GLT1/EAAT2 glutamate transporter in astrocytes, but the mechanisms were unknown. Thus, we decided to explore whether activation of the nuclear receptor peroxisome proliferator-activated receptor (PPAR) gamma, known for its antidiabetic and antiinflammatory properties, is involved in glutamate transport. First, we found that the PPARgamma antagonist T0070907 inhibits both IPC-induced tolerance and reduction of glutamate release after lethal oxygen-glucose deprivation (OGD) (70.1%+/-3.4% versus 97.7%+/-5.2% of OGD-induced lactate dehydrogenase (LDH) release and 61.8%+/-5.9% versus 85.9%+/-7.9% of OGD-induced glutamate release in IPC and IPC+T0070907 1 mumol/L, respectively, n=6 to 12, P<0.05), as well as IPC-induced astrocytic GLT-1 overexpression. IPC also caused an increase in nuclear PPARgamma transcriptional activity in neurons and astrocytes (122.1%+/-8.1% and 158.6%+/-22.6% of control PPARgamma transcriptional activity, n=6, P<0.05). Second, the PPARgamma agonist rosiglitazone increased both GLT-1/EAAT2 mRNA and protein expression and [(3)H]glutamate uptake, and reduced OGD-induced cell death and glutamate release (76.3%+/-7.9% and 65.5%+/-15.1% of OGD-induced LDH and glutamate release in rosiglitazone 1 mumol/l, respectively, n=6 to 12, P<0.05). Finally, we have identified six putative PPAR response elements (PPREs) in the GLT1/EAAT2 promoter and, consistently, rosiglitazone increased fourfold GLT1/EAAT2 promoter activity. All these data show that the GLT1/EAAT2 glutamate transporter is a target gene of PPARgamma leading to neuroprotection by increasing glutamate uptake.

Animals↗
PubMed2006

Increased body iron stores are associated with poor outcome after thrombolytic treatment in acute stroke.

BACKGROUND AND PURPOSE: Iron overload has been associated with greater oxidative stress and brain injury in experimental cerebral ischemia and reperfusion. This study investigates whether high serum ferritin levels, as an index of increased cellular iron stores, are associated with poor outcome, hemorrhagic transformation, and brain edema after treatment with tissue plasminogen activator in patients with acute ischemic stroke. METHODS: A total of 134 consecutive patients treated with intravenous tissue plasminogen activator were prospectively studied in four centers. Serum ferritin levels were determined at baseline, 24 and 72 hours after treatment. Cranial computed tomography was performed on admission and at 24 to 36 hours after tissue plasminogen activator infusion. Stroke severity and outcome were evaluated by using the National Institute of Health Stroke Scale and the modified Rankin Scale. RESULTS: Computed tomography showed hemorrhagic transformation in 27 patients (hemorrhagic infarction in 15 and parenchymal hematoma in 12; symptomatic in four) and brain swelling with midline shift in 15. Poor outcome (modified Rankin Scale >2) at 90 days was observed in 54.5% of patients. Ferritin levels at baseline were higher in patients with poor outcome at 90 days (median [quartiles], 165 [98,307] versus 17 [12,37] ng/mL; P<0.001) and in those who developed parenchymal hematoma (P=0.006), symptomatic hemorrhagic transformation (P=0.008), and severe brain edema (P<0.001). Serum ferritin levels higher than 79 ng/mL before tissue plasminogen activator treatment were independently associated with poor outcome (OR, 117 [95% CI, 25 to 557]). CONCLUSIONS: Increased body iron stores are associated with poor outcome, symptomatic hemorrhagic transformation, and severe edema in patients treated with tissue plasminogen activator after ischemic stroke. These findings suggest that iron overload may offset the beneficial effect of thrombolytic therapies.

Aged↗
PubMed2006

High blood pressure and inflammation are associated with poor prognosis in lacunar infarctions.

UNLABELLED: Lacunar infarction has long been considered to be associated with good prognosis, however a significant percentage of these patients remain functionally dependent. In this study we sought to investigate the factors associated with poor outcome in patients with lacunar infarction. SUBJECTS AND METHODS: We have performed a secondary study in 113 patients with lacunar infarctions admitted within the first 24 h of symptom onset (mean age 70 years, 57.5% men). Blood pressure, body temperature, serum glucose levels, neurotransmitters and pro-inflammatory markers were measured at admission and during the first 72 h. Stroke severity was assessed by the Canadian Stroke Scale (CSS). Neuroimaging evaluation was performed at admission and between days 4 and 7. Poor functional outcome was considered as a Barthel index <85 at 3 months. RESULTS: 36 patients (31.9%) had poor outcome. Older age (p = 0.009), history of hypertension (p = 0.005), higher body temperature (p < 0.0001), systolic blood pressure (SBP) (p = 0.010), serum glucose (p = 0.002) and interleukin-6 (IL-6) (p < 0.0001) levels, as well as lower CSS score at admission (p < 0.0001) were all predictive factors of poor outcome in bivariate analyses. SBP at admission (OR 2.07, CI 95% 1.04-3.28, p = 0.015) was the only clinical predictor on multivariate analysis. When the logistic model was further adjusted for biomarkers of inflammation and excitotoxicity, IL-6 levels (OR 1.09, CI 95% 1.01-1.26, p = 0.003), but not SBP, was independently associated with poor outcome. This association persisted even after adjusting for potential predictors recorded during the first 72 h of hospitalization. CONCLUSION: High SBP and IL-6 levels on admission may predict poor outcome in patients with lacunar infarction.

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PubMed2006

Deterioration in acute ischemic stroke as the target for neuroprotection.

The prevention and treatment of progressing stroke should be one of the main therapeutic targets of neuroprotective therapies. Despite the high prevalence of progressing stroke in acute stroke (25-35%) and its importance as a predictor of poor outcome, no treatment capable of preventing early neurological deterioration (END) or of reducing its impact has yet been developed. It is essential that our understanding of END's underlying mechanisms be improved as it is currently not possible to predict its occurrence accurately. Published studies to date have been unable to identify a clinical profile which reliably predicts those patients likely to suffer neurological deterioration in the very early acute phase of ischemic stroke. In the following pages, we will discuss the present situation with regard to neurological worsening in general, paying special attention to END given the prognostic and therapeutic implications of this common condition. Factors associated with neurological deterioration and the potential mechanisms, particularly excitotoxic theory, are discussed.

Animals↗
PubMed2006

A polymorphism in the EAAT2 promoter is associated with higher glutamate concentrations and higher frequency of progressing stroke.

It remains unclear why some individuals are susceptible to excitotoxicity after stroke. A possible explanation is impaired glutamate uptake. We have found a highly prevalent polymorphism in the promoter of the glutamate transporter EAAT2 gene that abolishes a putative regulatory site for activator protein-2 (AP-2) and creates a new consensus binding site for the repressor transcription factor GC-binding factor 2 (GCF2). The mutant genotype is associated with increased plasma glutamate concentrations and with a higher frequency of early neurological worsening in human stroke. After transfection into astrocytes, the mutant promoter was not activated by AP-2 and was effectively repressed by GCF2, and its activity in the presence of GCF2 was reduced when compared with the AP-2-cotransfected wild-type promoter. We also show that GCF2 is expressed in ischemic rat brain, suggesting that decreased glutamate uptake occurs in individuals carrying the mutation after stroke. These findings may explain individual susceptibility to excitotoxic damage after stroke as well as the failure of glutamate antagonists in those patients without this polymorphism.

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PubMed2006

Rosiglitazone and 15-deoxy-Delta12,14-prostaglandin J2 cause potent neuroprotection after experimental stroke through noncompletely overlapping mechanisms.

Stroke triggers an inflammatory cascade which contributes to a delayed cerebral damage, thus implying that antiinflammatory strategies might be useful in the treatment of acute ischaemic stroke. Since two unrelated peroxisome proliferator-activated receptor-gamma (PPARgamma) agonists, the thiazolidinedione rosiglitazone (RSG) and the cyclopentenone prostaglandin 15-deoxy-Delta(12,14)-prostaglandin J2 (15d-PGJ2), have been shown to possess antiinflammatory properties, we have tested their neuroprotective effects in experimental stroke. Rosiglitazone or 15d-PGJ2 were administered to rats 10 mins or 2 h after permanent middle cerebral artery occlusion (MCAO). Stroke outcome was evaluated by determination of infarct volume and assessment of neurological scores. Brains were collected for protein expression, gene array analyses and gene shift assays. Our results show that both compounds decrease MCAO-induced infarct size and improve neurological scores. At late times, the two compounds converge in the inhibition of MCAO-induced brain expression of inducible NO synthase and the matrix metalloproteinase 9. Interestingly, at early times, complementary DNA microarrays and gene shift assays show that different mechanisms are recruited. Analysis of early nuclear p65 and late cytosolic IkappaBalpha protein levels shows that both compounds inhibit nuclear factor-kappaB signalling, although at different levels. All these results suggest both PPARgamma-dependent and independent pathways, and might be useful to design both therapeutic strategies and prognostic markers for stroke.

Animals↗
PubMed2005

The prediction of malignant cerebral infarction by molecular brain barrier disruption markers.

BACKGROUND AND PURPOSE: Space-occupying brain edema is a life-threatening complication in patients with large hemispheric stroke. The aim of the study was to determine whether molecular markers of endothelial damage may help to predict secondary brain edema and, secondly, to identify patients who could benefit from aggressive therapies such as decompressive hemicraniectomy or hypothermia. METHODS: We studied 40 consecutive patients with malignant middle cerebral artery (MCA) infarction and 35 controls with massive MCA infarctions <70 years of age and matched by stroke severity on admission. Cranial computed tomography (CT) was performed at entry and repeated between days 4 and 7, or earlier if there was neurological worsening. Malignant MCA (m-MCA) infarction was diagnosed when follow-up CT detected a more than two-thirds space-occupying MCA infarction with midline shift, compression of the basal cisterns, and neurological deterioration. Plasma concentrations of glutamate, glycine, gamma-aminobutyric acid, interleukin-6 (IL-6), IL-10, tumor necrosis factor-alpha, matrix metalloproteinase-9 (MMP-9), and cellular-fibronectin (c-Fn) were determined in blood samples obtained at admission. RESULTS: Mean time from stroke onset to blood sampling was 6.3+/-4.8 in m-MCA and 7.7+/-6.0 hours in the control group (P=0.63). Baseline characteristics were comparable in both groups. c-Fn and MMP-9 levels were significantly higher in patients with m-MCA than in controls (all P<0.001). c-Fn >16.6 microg/mL had the highest sensitivity (90%), specificity (100%), and negative and positive predictive values (89% and 100%, respectively) for the prediction of m-MCA infarction. CONCLUSIONS: A plasma c-Fn concentration >16.6 microg/mL at admission is associated with the development of m-MCA infarction with high sensitivity and specificity, suggesting that c-Fn might be useful in therapeutic decision making.

Aged↗
PubMed2005

Increased plasma levels of 15-deoxyDelta prostaglandin J2 are associated with good outcome in acute atherothrombotic ischemic stroke.

BACKGROUND AND PURPOSE: The 15-deoxyDelta prostaglandin J2 (15-dPGJ2) is an anti-inflammatory prostaglandin that has been proposed to be the endogenous ligand of peroxisome proliferator-activated receptor-gamma (PPARgamma), a nuclear receptor that can exert potent anti-inflammatory actions by repressing inflammatory genes when activated. It has been suggested that 15-dPGJ2 could be beneficial in neurological disorders in which inflammation contributes to cell death such as stroke. METHODS: We investigated the relationship between plasma levels of 15-dPGJ2 and early neurological deterioration (END), infarct volume, and neurologic outcome in 552 patients with an acute stroke admitted within 24 hours after symptoms onset. RESULTS: Median [quartiles] plasma 15-dPGJ2 levels on admission were significantly higher in patients than in controls (60.5 [11.2 to 109.4] versus 5.0 [3.8 to 7.2] pg/mL; P<0.0001). Levels of this prostaglandin were also significantly higher in patients with vascular risk factors (history of hypertension or diabetes) and with atherothrombotic infarcts (113.9 [81.6 to 139.7] pg/mL), than in those with lacunar (58.7 [32.7 to 86.2] pg/mL), cardioembolic (12.1 [6.5 to 39.2] pg/mL), or undetermined origin infarcts (11.4 [5.6 to 24.3] pg/mL) (P<0.0001). In the subgroup of patients with atherothrombotic infarcts, the adjusted odds ratio of END and poor outcome for 1 pg/mL increase in 15-dPGJ2 were 0.95 (95% CI, 0.94 to 0.97) and 0.97 (95% CI, 0.96 to 0.98), respectively. In a generalized linear model, by 1 U increase in 15-dPGJ2, there was a reduction of 0.47 mL (95% CI, 0.32 to 0.63) in the mean estimated infarct volume. CONCLUSIONS: Increased plasma 15-dPGJ2 concentration is associated with good early and late neurological outcome and smaller infarct volume. These findings suggest a neuroprotective effect of 15-dPGJ2 in atherothrombotic ischemic stroke.

Acute Disease↗
PubMed2004

Semi-intensive monitoring in acute stroke and long-term outcome.

BACKGROUND AND PURPOSE: Factors that determine the benefit of stroke units (SU) are unknown. The aim of our study was to analyze whether semi-intensive monitoring during the acute phase of stroke reduces mortality and dependency at long term. METHODS: We studied patients with an ischemic stroke or intracerebral hemorrhage, consecutively admitted to our SU within 24 h of symptoms onset. Based on bed availability, patients were allocated to either a conventional care stroke unit (C-SU, n = 209) or a semi-intensive stroke unit (SI-SU, n = 321) with continuous monitoring of cardiac, respiratory, metabolic and neurological functions during the first 72 h. Both groups were treated following the same medical and nursing protocols. Criteria for exclusion were patients with stupor/coma, previously dependent (Barthel score <85) and with TIA. Using logistic regression models, we analyzed the influence of semi-intensive care on mortality and dependency at one year. RESULTS: Baseline characteristics were similar between patients admitted to the SI-SU and the C-SU, except for a higher frequency of more severe stroke and intracerebral hemorrhage in the SI-SU. Twenty-six percent of patients in the SI-SU and 4% in the C-SU were randomized in acute clinical trials (p < 0.01), and 61% and 39% were seen by a neurologist in less than 6 h from the onset of symptoms (p < 0.01). At 1 year, mortality and combined mortality and dependency were not significantly different between the two groups. However, due to the presence of a significant interaction between the type of unit and stroke severity, the OR of mortality for SI-SU allocation was 0.19 (95% CI, 0.07-0.54) in patients with severe stroke (CSS < or =4), whereas it was 0.64 (95% CI, 0.37-1.11) in those with mild-to-moderate stroke. CONCLUSIONS: This study suggests that semi-intensive monitoring in a stroke unit reduces mortality at 1 year in patients with severe stroke, with no influence over dependency.

Acute Disease↗
PubMed2004

Comparison of preperfusion and postperfusion magnetic resonance angiography in acute stroke.

BACKGROUND AND PURPOSE: The multimodal magnetic resonance imaging study in acute stroke includes perfusion-weighted imaging (PWI) after administration of contrast and magnetic resonance angiography (MRA). However, MRA may overestimate the degree of vessel obstruction caused by limitations to detect low flow states. Our aim was to determine the usefulness of a new fast imaging protocol combining classical MRA, PWI, and postperfusion MRA to improve the diagnostic management in acute ischemic stroke. METHODS: We studied 31 patients with a middle cerebral artery (MCA) infarction within the first 12 hours from the onset of symptoms. All patients had an MCA stenosis or occlusion. The study protocol included a preperfusion MRA and a postperfusion MRA. Modified thrombolysis in myocardial infarction (TIMI) classification was used to assess the patency of vessels. RESULTS: In 17 patients (group A, 55%), preperfusion MRA and postperfusion MRA accorded in the estimation of vascular status, whereas in 14 patients (group B, 45%) postperfusion MRA showed a better vascular flow than preperfusion MRA. The improvement in the depiction of flow was from a complete occlusion (TIMI I) to a partial occlusion (TIMI II) in 9 patients and from TIMI II to normal patency (TIMI III) in 5 patients. Thirty-six percent of the patients with suspected internal carotid artery occlusion in the preperfusion MRA showed flow in the intracranial internal carotid artery in the postperfusion MRA. CONCLUSIONS: Postperfusion contrast-enhanced MRA can demonstrate arterial segments with low flow and avoid overestimation of vascular obstruction.

Acute Disease↗
PubMed2004

Plasma cellular-fibronectin concentration predicts hemorrhagic transformation after thrombolytic therapy in acute ischemic stroke.

BACKGROUND AND PURPOSE: Elevated plasma levels of cellular fibronectin (c-Fn) reflect vascular damage, so c-Fn might be a marker of secondary bleeding risk in cerebral ischemia. We investigated whether high plasma levels of c-Fn were associated with hemorrhagic transformation (HT) after treatment with tissue plasminogen activator (tPA) in patients with acute stroke. METHODS: Eighty-seven patients (mean age: 67+/-12) received tPA after the ECASS II criteria (mean time to infusion: 160+/-46 minutes; median NIHSS: 12). HT and hypodensity volume were studied on computed tomography (CT) performed 24 to 36 hours after treatment. HT was classified according to the ECASS II definitions. c-Fn and matrix metalloproteinase 9 (MMP-9) levels were determined by ELISA in blood samples obtained before treatment and in 30 healthy subjects. RESULTS: HT was found in 26 patients (30%); 15 patients had hemorrhagic infarction type 1 (HI-1), 7 had HI-2, and 4 had parenchymal hemorrhage (PH). Median c-Fn concentrations were 1.3, 1.7, 4.2, 5.4, and 7.3 microg/mL in controls, non-HT, HI-1, HI-2, and PH groups, respectively (P<0.001); median MMP-9 values were 54, 87, 154, 176, and 225 ng/mL (P<0.001). Logistic regression analysis showed that only c-Fn plasma levels remained independently associated with HT after adjusting for potential confounders (OR, 2.1; 95% CI, 1.3 to 3.4; P=0.002). Similar results were obtained in the 71 patients treated within 3 hours. CONCLUSIONS: High plasma c-Fn levels are significantly associated with subsequent HT in stroke patients treated with tPA, so plasma c-Fn determinations might be useful in clinical practice to improve the risk/benefit ratio of thrombolytic treatment.

Aged↗
PubMed2004

Blood pressure decrease during the acute phase of ischemic stroke is associated with brain injury and poor stroke outcome.

BACKGROUND AND PURPOSE: Studies on the relation between blood pressure (BP) and stroke outcome have shown contradictory results. We explored the association of systolic (SBP) and diastolic (DBP) BP during acute stroke with early neurological deterioration, infarct volume, neurological outcome, and mortality at 3 months. METHODS: We included 304 patients with acute ischemic stroke. SBP and DBP on admission and on the first day were the average values of all readings obtained in the emergency department and during a 24-hour period after patient allocation in the stroke unit. RESULTS: A U-shaped effect was observed: for every 10 mm Hg 180 mm Hg, the risk of early neurological deterioration increased by 40% and the risk of poor outcome increased by 23%, with no effect on mortality. Mean infarct volume increased 7.3 and 5.5 cm(3) for every 10 mm Hg 180 mm Hg. A similar pattern was found in patients with DBP 100 mm Hg. These effects disappeared after adjustment for the use of antihypertensive drugs and BP drop >20 mm Hg within the first day, with the latter being the more important prognostic factor of poor outcome. CONCLUSIONS: High and low SBP and DBP, as well as a relevant drop in BP, are associated with poor prognosis in patients with ischemic stroke.

Acute Disease↗
PubMed2004

Cerebral hemodynamic reserve and early neurologic deterioration in acute ischemic stroke.

Early neurological deterioration (END) is associated with increased mortality and morbidity. Although several predictive factors have been reported, there are little data about the hemodynamic factors. Our aim was to determine the capacity of cerebral hemodynamic reserve (CHR) to predict END. We studied 100 hospitalized patients with a first ever ischemic stroke of the middle cerebral artery (MCA) within the first 24 hours of symptoms onset. END was defined as a drop of at least one point in the Canadian Stroke Scale between admission and 72 hours. The mean flow velocity (mV) in the MCA and the CHR were measured by means of transcranial Doppler within the first 24 hours of admission. The CHR was expressed as the percentage increase in the MCA mV divided by the absolute increase in the end-tidal CO2 pressure in mm Hg after carbogen inhalation. END was observed in 23 patients. Reduced values of the mV in the symptomatic MCA (P = 0.043) and of the CHR in the symptomatic hemisphere (P < 0.001) were significantly associated with END. A CHR of less than 2%/1 mm Hg was independently associated with END (OR 8.45, 95% CI 1.82-39.2) after adjusting for potential confounders. CHR impairment within the first 24 hours of acute ischemic stroke is associated with a higher risk of END. This technique may be useful in selecting patients requiring a more intensive management.

Aged↗
PubMed2003

Neuroprotective effects of aspirin in patients with acute cerebral infarction.

Aspirin may reduce ischemic brain injury. The aim of this study was to explore the effect of aspirin on glutamate release after acute stroke. We studied 238 patients with a first episode of hemispheric ischemic stroke of less than 24 h duration. Early neurological deterioration was diagnosed when the Canadian Stroke Scale dropped 1 or more points between admission and 48 h. Glutamate was determined on cerebrospinal fluid (CSF) samples obtained at admission. Sixty-three patients were undergoing treatment with 75-500 mg/day of aspirin at the time of stroke onset. CSF glutamate concentrations were higher in the group of patients not taking aspirin (8.9+/-5.2 vs. 4.9+/-3.1 microM/l, P< 0.0001). Aspirin treatment at stroke onset had a 97% risk reduction of early neurological deterioration, and this effect remained unchanged after a further adjustment for glutamate concentrations. These findings suggest that low doses of aspirin may be useful in the management of patients with cerebral ischemia, not only for its antithrombotic properties, but also by direct neuroprotective effects.

Acute Disease↗
PubMed2003

The release of tumor necrosis factor-alpha is associated with ischemic tolerance in human stroke.

Tumor necrosis factor (TNF)-alpha overexpression has been related to experimental ischemic tolerance when transient ischemia precedes cerebral infarction. We investigated TNF-alpha and interleukin (IL)-6 plasma concentrations in 283 patients with an acute stroke within 24 hours after symptom onset. An ipsilateral transient ischemic attack (TIA) within 72 hours before stroke was recorded in 38 patients. The infarct volume measured on computed tomography on days 4 to 7 and the frequency of poor outcome (Barthel Index score < 85) at 3 months were significantly lower in patients with prior TIA. Plasma concentrations of TNF-alpha were higher (42.5 +/- 9.9 vs 13.1 +/- 6.4pg/ml, p < 0.0001) and IL-6 levels were lower (10.1 +/- 6.2 vs 28.3 +/- 17.3pg/ml, p < 0.0001) in patients with prior TIA. A new variable termed TNF-alpha/IL-6 index was considered positive when TNF-alpha was greater than 30pg/ml and IL-6 was less than 30pg/ml. Positive TNF-alpha/IL-6 index was found in 92% of patients with prior TIA and in 1% of those without. TNF-alpha/IL-6 index (p = 0.0003) and TIA (p = 0.0001) were associated with good outcome in logistic regression analysis after adjusting for potential confounding factors. Ischemic tolerance in acute stroke is associated with increased plasma levels of TNF-alpha in the presence of reduced concentrations of IL-6.

Aged↗
PubMed2003

Stroke on awakening: looking for a more rational management.

BACKGROUND AND PURPOSE: Stroke on awakening (SOA) is denied the benefits of thrombolytic therapy and is typically excluded from acute clinical trials on the grounds that the time of onset is unknown. In this study we compared the clinical characteristics of SOA and of stroke while awake (SWA), particularly in the subgroup of patients seen within a time frame of 6 h after stroke awareness. MATERIAL AND METHODS: Patients were included consecutively in the Stroke Data Bank of the Spanish Neurological Society (BADISEN) that records 365 different items, including vascular risk factors, neurological findings, stroke severity, aetiopathogenic diagnosis and neuroimaging data. RESULTS: A total of 1,248 patients with acute cerebral infarction were included in the study, 301 (24.1%) with SOA and 947 (75.9%) with SWA. The peak time for stroke occurrence was between 6:01 a.m. and 12 noon, both in the whole stroke group and in each aetiopathogenic stroke subtype. Age, sex, stroke risk factors, stroke severity at admission, vital signs and stroke subtypes were not significantly different between SOA and SWA, neither in the group as a whole nor in the group of patients seen within 6 h of stroke recognition. Six hundred and fifty-four patients were seen within the potential 6-hour therapeutic window. In this group, the CT scan on admission was normal in 39.4% of SOA but the ultimate CT/MRI scan showed that 46.2% of these had a territorial infarction (in SWA these same figures were 60.8 and 67.7%, respectively). CONCLUSION: There are no relevant differences in the clinical, neuroimaging and aetiopathogenic characteristics of SOA and SWA. We should rely on new techniques such as DWI/PWI to indicate the most appropriate treatment in a more rational manner as nearly half of the patients with SOA seen early may benefit from them.

Aged↗
PubMed2003

Plasma metalloproteinase-9 concentration predicts hemorrhagic transformation in acute ischemic stroke.

BACKGROUND AND PURPOSE: Matrix metalloproteinase-9 (MMP-9) activity has been associated with hemorrhagic transformation (HT) in experimental models of cerebral ischemia. Our aim was to investigate the relationship between MMP-9 concentrations in blood within 24 hours of stroke onset and subsequent HT of cerebral infarction. METHODS: We studied 250 patients with a hemispheric ischemic stroke of 7.8+/-4.5 hours' duration. Early CT signs of cerebral infarction were evaluated on admission. The HT and infarct volume were analyzed from the CT performed on days 4 through 7. MMP-9 levels were determined by enzyme-linked immunosorbent assay in blood samples obtained on admission. RESULTS: HT was observed in 38 patients (15.2%): 24 (63.2%) had a hemorrhagic infarction, and 14 (36.8%) had a parenchymal hematoma. A total of 108 patients (43%) received anticoagulants before the second CT scan. Systolic and diastolic blood pressures, body temperature, frequency of early CT signs of ischemia (92% versus 22%), and treatment with anticoagulants (79% versus 37%) were significantly higher in the group with HT (P<0.001). Mean infarct volume was 126+/-60 cm(3) in the HT group and 90+/-68 cm3 in the group without HT (P=0.003). Median (quartiles) plasma MMP-9 concentrations were higher in the HT group (193 [163, 213] versus 62 [40, 93] ng/mL, P<0.001), even in the 24 patients seen within 3 hours of symptom onset (P=0.014). MMP-9 levels > or =140 ng/mL had a positive and negative predictive value of HT of 61% and 97%, respectively. MMP-9 > or =140 ng/mL was associated with HT (odds ratio, 12; 95% confidence interval, 3 to 51; P<0.001) after adjustment for potential confounders and final infarct volume. CONCLUSIONS: High plasma MMP-9 concentration in the acute phase of a cerebral infarct is an independent biochemical predictor of HT in all stroke subtypes.

Biomarkers↗