We have undertaken a prospective study to measure anticardiolipin antibodies of IgG isotype within the first few hours of an acute non-hemorrhagic stroke.
We have collected blood samples at entry ...from one hundred patients (53 men and 47 women), mean age 67.4 years, referred within 6 h of a first-ever non-hemorrhagic stroke, and from an equal number of age- and gender-matched control patients.
IgG anticardiolipin antibodies were > or = 10 GPL in 26 patients and in 5 controls (p < 0.0001, X2 test). After logistic regression analysis, increase of IgG anticardiolipin antibodies remained independently associated with stroke (p = 0.0034), together with hypertension (p = 0.0009) and atrial fibrillation (p = 0.0238).
Our data suggest that the occurrence of elevation of IgG anticardiolipin antibodies in stroke patients should antedate stroke onset and might be a risk factor per se.
We prospectively verified whether an ad-hoc questionnaire administered by phone supports pre-hospital suspicion of stroke in order to reduce the time before care is given. From June 1996 to May 1997, ...physicians of the Emergency Medical Service in the area of Bergamo, Italy asked all people calling for a patient with symptoms and signs suggesting a cerebral vascular injury to immediately answer some questions on common symptoms and signs of stroke. The medical records of the patients hospitalized at Ospedali Riuniti of Bergamo were reviewed at the end of the study by a single neurologist, skilled in stroke management and blinded to the questionnaires. Sensitivity and specificity, in addition to positive and negative predictive values, of single questions versus final diagnosis were assessed. Logistic regression analysis was also performed to identify those questions useful to suspect strokes. We collected 143 valid questionnaires, related to 63 men and 80 women, aged 34-99 years (mean, 71.8 years). The question concerning headache had the lowest sensitivity and specificity, respectively 57.1% and 36.5%, and the question concerning leg palsy had the highest sensitivity and specificity, respectively 82.0% and 52.4%. Multivariate analysis identified questions on facial and leg palsy as independent predictors of a final diagnosis of stroke. A few questions on motor deficits proposed by emergency medical service operators may be useful in the pre-hospital identification of stroke patients. Concordance of any questions versus final diagnosis of stroke was, however, far to be satisfying. Thus, our experience supports the need for an educational program to improve the efficiency of a pre-hospital diagnosis of stroke.
We have investigated the reliability of transcranial doppler compared with cerebral angiography in acute ischemic stroke in the middle cerebral artery territories. We studied 48 patients, 28 men and ...21 women, mean age 68.1 (range 54-75), observed within 5 h of the onset of ischemic stroke in the middle cerebral artery territory. Ultrasound evaluation (duplex scanner and transcranial doppler) and cerebral angiography were carried out in close sequence immediately after CT scan. CT was repeated by Day 7 to estimate the infarct size: 27/48 patients had intracranial arterial obstructions. An acoustic temporal "window" was not found in 6.25%. Transcranial doppler showed a sensitivity of 80.0% and a specificity of 90.0% compared with cerebral Angiography for patients with patent acoustic temporal "windows". Accuracy was 79.2%, when patients with no "windows" were included. With respect to intracranial internal carotid artery and middle cerebral artery mainstem, transcranial doppler showed a sensitivity of 95.0%, and a specificity of 92.0%. Including patients with no windows, accuracy was 87.5%.
Our data suggest that Transcranial Doppler can be reliably used to demonstrate intracranial internal carotid artery or middle cerebral artery mainstem obstructions in the acute phase of a brain infarction.
Objective– To assess if Doppler microembolic signals (MES) associated with ≥60% symptomatic extracranial carotid stenosis may predict ischemic recurrences before endarterectomy or angioplasty. ...Methods– All patients with ≥60% carotid stenosis with symptoms in the preceding 2 months were prospectively considered. MES were identified using current criteria. All patients were followed‐up until endarterectomy or angioplasty. Results– We studied 50 patients, at a median of 7 days from their last symptom. Twenty patients showed MES (40.0%); median embolus rate was 4/h. During a median follow‐up of 19 days 7 patients had recurrences (transient monocular blindness=2; TIAs=4; stroke=1); 6 of them had shown MES. The association between recurrences and MES was significant (P=0.012). Conclusions– MES may identify patients with symptomatic carotid stenosis who are likely to suffer an ischemic recurrence before endarterectomy. This information may affect medical treatment and referral to the vascular surgeon.
CrSiTe{sub 3} has attracted recent interest as a candidate single-layer ferromagnetic semiconductor, but relatively little is known about the bulk properties of this material. Here, we report ...single-crystal X-ray diffraction, magnetic properties, thermal conductivity, vibrational, and optical spectroscopies and compare our findings with complementary electronic structure and lattice dynamics principles calculations. The high temperature paramagnetic phase is characterized by strong spin-lattice interactions that give rise to glassy behavior, negative thermal expansion, and an optical response that reveals that CrSiTe{sub 3} is an indirect gap semiconductor with indirect and direct band gaps at 0.4 and 1.2 eV, respectively. Measurements of the phonons across the 33 K ferromagnetic transition provide additional evidence for strong coupling between the magnetic and lattice degrees of freedom. The Si-Te stretching and Te displacement modes are sensitive to the magnetic ordering transition, a finding that we discuss in terms of the superexchange mechanism. Spin-lattice coupling constants are also extracted.
Dementia after first stroke CENSORI, B; MANARA, O; MAMOLI, A ...
Stroke (1970),
07/1996, Letnik:
27, Številka:
7
Journal Article
Recenzirano
Cognitive deficits may significantly worsen the quality of life after stroke. Our aim was to determine the frequency of dementia in a consecutive series of previously nondemented patients between the ...ages of 40 and 79 years at 3 months after a first ischemic stroke.
All patients admitted to our department during an 18-month period who met the above criteria were visited and tested and underwent a CT scan 3 months after their stroke. Dementia was diagnosed according to criteria of the National Institute of Neurological Disorders and Stroke and AIREN, but cases with aphasia were not excluded.
Of 304 patients admitted for stroke, 146 were eligible for study. Eleven refused to participate, 25 were dead at 3 months, and 110 were tested. Fifteen patients were demented (13.6%; 95% confidence interval CI, 7.8% to 21.5%), and six had severe isolated aphasia, neglect, or memory deficit (5.4%). Excluding patients with aphasia, 5.0% of cases showed dementia (95% CI, 1.6% to 11.3%). The frequency of dementia was 24.6% (95% CI, 14.5% to 37.3%), considering only patients with supratentorial lesions and with residual deficits of elementary functions (paresis, sensory deficits) at the time of examination. Demented patients had significantly more diabetes (P<.029), atrial fibrillation (P=.032), aphasia at entry (P<.001), large middle cerebral artery infarctions (P=.001), and a more severe neurological deficit at entry (P=.003) and at 3 months (P=.001). At CT scan, demented patients had a larger mean volume of the recent lesion (P<.001) and more lesions in the frontal lobe (P=.041). An exploratory multivariate analysis selected age between 60 and 69 years (odds ratio OR, 45.8; 95% CI, 2.9 to 726.0), diabetes (OR 59.4; 95% CI, 4.3 to 821.0), aphasia (OR, 14.8; 95% CI, 2.0 to 111.0), a large middle cerebral artery infarction (OR, 30.0; 95% CI, 2.7 to 334.0), and lesions of the frontal lobe (OR, 9.8; 95% CI, 1.3 to 72.8) as significant independent correlates of poststroke dementia.
Dementia is relatively frequent after a clinical first stroke in persons younger than 80 years, and aphasia is very often associated with poststroke dementia. If aphasic patients are not considered, it may be necessary to screen a very large number of subjects to collect an adequate sample of demented cases.
The efficacy of oral anticoagulant therapy in reducing the risk of stroke and systemic embolism has been demonstrated for both primary and secondary prevention in patients with nonrheumatic atrial ...fibrillation. Reductions in the risk of thromboembolic events (usually defined as ischemic stroke and systemic embolism) range from 37 to 86 percent, but major bleeding complications occur at rates of 5 to 28 per 1000 patient-years.
1
–
7
However, the targeted therapeutic ranges, as well as the levels of anticoagulant control actually obtained, differed widely among studies. In primary-prevention trials, for example, 8 to 40 percent of the international normalized ratios (INRs) . . .
Anti-Purkinje cell antibodies (APCA), believed to be markers of paraneoplastic cerebellar degeneration in females, have been identified in the serum of 3 men with subacute sensory neuronopathies and ...no evidence of tumors 5 years after the onset of the neurological signs. By indirect immunohistochemistry on sections of rat cerebellum and dorsal root ganglia, the patients' IgG bound to the cytoplasms of both Purkinje cells and dorsal root ganglia neurons. By western blot analysis on whole human cerebellum and whole human dorsal root ganglia homogenates, the IgG from 2 patients bound to a 62-kd protein in both homogenates and the IgG from 1 patient bound to a 110-kd protein in the cerebellum homogenate only. Yo autoantibody test was negative in all patients. Our study provides evidence that non-anti-Yo APCA may be associated with subacute sensory neuronopathies and are not necessarily markers of an underlying tumor. The previously described anti-Yo APCA has only occurred in females with cancer.
Abstract
Sorghum bicolor
is a drought‐resilient C4 grass used for production of grain, forage, sugar, and biomass. Sorghum genotypes capable of accumulating high levels of stem sucrose have solid ...stems that contain low levels of aerenchyma. The
D
‐locus on
<styled-content style='fixed-case'>SBI</styled-content>
06 modulates the extent of aerenchyma formation in sorghum stems and leaf midribs. A
<styled-content style='fixed-case'>QTL</styled-content>
aligned with this locus was identified and fine‐mapped in populations derived from
<styled-content style='fixed-case'>BT</styled-content>
x623*
<styled-content style='fixed-case'>IS</styled-content>
320c,
<styled-content style='fixed-case'>BT</styled-content>
x623*R07007, and
<styled-content style='fixed-case'>BT</styled-content>
x623*Standard broomcorn. Analysis of coding polymorphisms in the fine‐mapped
D
‐locus showed that genotypes that accumulate low levels of aerenchyma encode a truncated
<styled-content style='fixed-case'>NAC</styled-content>
transcription factor (Sobic.006G147400,
SbNAC_d1
), whereas parental lines that accumulate higher levels of stem aerenchyma encode full‐length
<styled-content style='fixed-case'>NAC TF</styled-content>
s (
SbNAC‐D
). During vegetative stem development, aerenchyma levels are low in nonelongated stem internodes, internode growing zones, and nodes. Aerenchyma levels increase in recently elongated internodes starting at the top of the internode near the center of the stem.
SbNAC_D
was expressed at low levels in nonelongated internodes and internode growing zones and at higher levels in regions of stem internodes that form aerenchyma.
SbXCP1
, a gene encoding a cysteine protease involved in programmed cell death, was induced in
SbNAC_D
genotypes in parallel with aerenchyma formation in sorghum stems but not in
SbNAC_d1
genotypes. Several sweet sorghum genotypes encode the recessive
SbNAC_d1
allele and have low levels of stem aerenchyma. Based on these results, we propose that
SbNAC_D
is the
D
‐gene identified by Hilton (1916) and that allelic variation in
SbNAC_D
modulates the extent of aerenchyma formation in sorghum stems.
This paper explores basic aspects of the immune system and proposes a novel immune network model with the main goals of clustering and filtering unlabelled numerical data sets. It is not our concern ...to reproduce with confidence any immune phenomenon, but to show that immune concepts can be used to develop powerful computational tools for data processing. As important results of our model, the network evolved will be capable of reducing redundancy, describing data structure, including the shape of the clusters. The network will be implemented in association with a statistical inference technique, and its performance will be illustrated using two benchmark problems. The paper is concluded with a trade-off between the proposed network and artificial neural networks used to perform unsupervised learning.
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