281 research outputs found
Life-threatening orolingual angioedema during thrombolysis in acute ischemic stroke
Background: Orolingual angioedema can occur during thrombolysis with alteplase in stroke patients. However, data about its frequency, severity and the significance of concurrent use of angiotensin-converting-enzyme inhibitors (ACEi) are sparse. Objective: (1), to alert to the potentially life-threatening complication of orolingual angioedema. (2), to present CT-scans of the tongue which exclude lingual hematoma. (3), to estimate the frequency of orolingual angioedema. (4), to evaluate the risk associated with the concurrent use of ACEi. Methods: Single center, databank-based observational study on 120 consecutive patients with i. v. alteplase for acute stroke. Meta-analysis of all stroke studies on alteplase-associated angioedema, which provided detailed information about the use of ACEinhibitors. Across studies, the Peto odds ratio of orolingual angioedema for "concurrent use of ACEi" was calculated. Results: Orolingual angioedema occurred in 2 of 120 patients (1.7%, 95% CI 0.2-5.9 %).Angioedema was mild in one, but rapidly progressive in another patient. Impending asphyxia prompted immediate intubation. CT showed orolingual swelling but no bleeding. One of 19 (5%) patients taking ACEi had orolingual angioedema, compared to 1 of 101 (1%) patients without ACEi. Medline search identified one further study about the occurrence of alteplase-associated angioedema in stroke patients stratified to the use of ACEi. Peto odds ratio of 37 (95 % CI 8-171) indicated an increased risk of alteplasetriggered angioedema for patients with ACEi (p <0.001). Conclusion: Orolingual angioedema is a potentially life-threatening complication of alteplase treatment in stroke patients, especially in those with ACEi. Orolingual hematoma as differential diagnosis can be excluded by CT-sca
Abnormal Visuo-vestibular Interactions in Vestibular Migraine: a Cross Sectional Study
Vestibular migraine is amongst the commonest causes of episodic vertigo. Chronically, patients with vestibular migraine develop abnormal responsiveness to both vestibular and visual stimuli characterised by heightened self-motion sensitivity and visually-induced dizziness. Yet, the neural mechanisms mediating such symptoms remain unknown. We postulate that such symptoms are attributable to impaired visuo-vestibular cortical interactions, which in-turn disrupts normal vestibular function. To assess this, we investigated whether prolonged, full-field visual motion exposure, which has previously been shown to modulate visual cortical excitability in both healthy individuals and avestibular patients, could disrupt vestibular ocular reflex (VOR) and vestibular-perceptual thresholds of self-motion during rotations. Our findings reveal that vestibular migraine patients exhibited abnormally elevated reflexive and perceptual vestibular thresholds at baseline. Following visual motion exposure, both reflex and perceptual thresholds were significantly further increased in vestibular migraine patients relative to healthy controls, migraineurs without vestibular symptoms and patients with episodic vertigo due to a peripheral inner-ear disorder. Our results provide support for the notion of altered visuo-vestibular cortical interactions in vestibular migraine, as evidenced by vestibular threshold elevation following visual motion exposure
Recurrent stroke risk and cerebral microbleed burden in ischemic stroke and TIA A meta-analysis
OBJECTIVE: To determine associations between cerebral microbleed (CMB) burden with recurrent
ischemic stroke (IS) and intracerebral hemorrhage (ICH) risk after IS or TIA.
METHODS: We identified prospective studies of patients with IS or TIA that investigated CMBs and
stroke (ICH and IS) risk during 5 CMBs)
and distribution. We calculated absolute event rates and pooled risk ratios (RR) using randomeffects
meta-analysis.
RESULTS: We included 5,068 patients from 15 studies. There were 115/1,284 (9.6%) recurrent IS
events in patients with CMBs vs 212/3,781 (5.6%) in patients without CMBs (pooled RR 1.8 for
CMBs vs no CMBs; 95% confidence interval [CI] 1.4–2.5). There were 49/1,142 (4.3%) ICH
events in those with CMBs vs 17/2,912 (0.58%) in those without CMBs (pooled RR 6.3 for CMBs
vs no CMBs; 95% CI 3.5–11.4). Increasing CMB burden increased the risk of IS (pooled RR [95%
CI] 1.8 [1.0–3.1], 2.4 [1.3–4.4], and 2.7 [1.5–4.9] for 1 CMB, 2–4 CMBs, and 5 CMBs, respectively).
CONCLUSIONS: CMBs are associated with increased stroke risk after IS or TIA. With increasing CMB
burden (compared to no CMBs), the risk of ICH increases more steeply than that of IS. However, IS
absolute event rates remain higher than ICH absolute event rates in all CMB burden categories
Measurement of the proton and deuteron structure functions, F2p and F2d, and of the ratio sigma(L)/sigma(T)
The muon-proton and muon-deuteron inclusive deep inelastic scattering cross
sections were measured in the kinematic range 0.002 < x < 0.60 and 0.5 < Q2 <
75 GeV2 at incident muon energies of 90, 120, 200 and 280 GeV. These results
are based on the full data set collected by the New Muon Collaboration,
including the data taken with a small angle trigger. The extracted values of
the structure functions F2p and F2d are in good agreement with those from other
experiments. The data cover a sufficient range of y to allow the determination
of the ratio of the longitudinally to transversely polarised virtual photon
absorption cross sections, R= sigma(L)/sigma(T), for 0.002 < x < 0.12 . The
values of R are compatible with a perturbative QCD prediction; they agree with
earlier measurements and extend to smaller x.Comment: In this replacement the erroneously quoted R values in tables 3-6 for
x>0.12, and R1990 values in tables 5-6 for all x, have been corrected, and
the cross sections in tables 3-4 have been adapted. Everything else,
including the structure functions F2, remained unchanged. 22 pages, LateX,
including figures, with two .sty files, and three separate f2tab.tex files
for the F2-tables. Accepted for publication in Nucl.Phys.B 199
Debye-Hueckel solution for steady electro-osmotic flow of a micropolar fluid in a cylindrical microcapillary
Analytic expressions for the speed, flux, microrotation, stress, and couple
stress in a micropolar fluid exhibiting steady, symmetric and one-dimensional
electro-osmotic flow in a uniform cylindrical microcapillary were derived under
the constraint of the Debye-Hueckel approximation, which is applicable when the
cross-sectional radius of the microcapillary exceeds the Debye length, provided
that the zeta potential is sufficiently small in magnitude. As the aciculate
particles in a micropolar fluid can rotate without translation, micropolarity
influences fluid speed, fluid flux, and one of the two non-zero components of
the stress tensor. The axial speed in a micropolar fluid intensifies as the
radius increases. The stress tensor is confined to the region near the wall of
the microcapillary but the couple stress tensor is uniform across the
cross-section.Comment: 19 page
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