Recanalization with Wingspan stent for acute middle cerebral artery occlusion in failure or contraindication to intravenous thrombolysis: a feasibility study

BACKGROUND AND PURPOSE

Recanalization with the Wingspan stent, which can be deployed rapidly and safely, is an option for treating acute ischemic stroke when intravenous thrombolysis has failed or is contraindicated. This study was performed to evaluate feasibility, efficacy, and safety of recanalization for acute middle cerebral artery occlusion using the Wingspan stent.

MATERIALS AND METHODS

We collected 10 patients with acute MCA occlusion in whom recanalization was not achieved with a standard intravenous thrombolysis, or who were ineligible for intravenous thrombolysis, or who presented after 3 hours of symptom onset and in whom the stent placement could be completed within 8 hours from symptom onset. We analyzed angiographic and clinical results.

RESULTS

Successful recanalization with the Wingspan stent was achieved in all patients. The mean NIHSS score on admission was 12.7 points (range 4-21). The occlusion sites were located in the 1st segment (n = 7; 2 left, 5 right) and 2nd segment (n = 3, all right) of the MCA. The mean time interval from stroke symptom onset to stent placement was 344.8 ± 76.3 minutes. No intracranial hemorrhage, vessel perforations, or dissections occurred in any patient. Nine patients improved on the NIHSS at 7 days. One patient did not have a change in the NIHSS score, even though the occluded artery was completely recanalized. At 7 days, the NIHSS score of all patients was 4.4 ± 4.7 (median 4, range 0-13). At discharge, an mRS of ≤ 3 was achieved in all patients and an mRS of ≤ 2 was achieved in 7 patients (70%).

CONCLUSIONS

This small case series demonstrates the feasibility of using the Wingspan stent safely and effectively for MCA occlusions when standard treatments are ineffective or not available.

Attentional distractibility by optokinetic stimulation in Alzheimer disease

OBJECTIVE

Unilateral temporoparietal injury may result in an attentional deficit for stimuli presented in contralesional space. Thus, bilateral temporoparietal degeneration associated with Alzheimer disease (AD) might result in a bilateral attentional disturbance. Tests for hemispatial neglect, however, primarily assess spatial attentional asymmetries, and a bilateral attentional disorder might not be detected with these tests. The goal of this study was to learn whether optokinetic stimulation (OKS) would perturb the balanced attentional deficits of AD patients and alter their spatial allocation of attention.

METHODS

In Experiment I, 10 AD patients with bilateral temporoparietal glucose hypometabolism on PET and 10 controls bisected lines in two conditions: stationary solid lines superimposed on a moving background and "striped lines" where the whole line was stationary but the stripes within the line moved. The background OKS or the stripes within the line moved leftward or rightward or were stationary. In Experiment II, to investigate whether the influence of background movements would increase with AD severity, we conducted a similar experiment in 56 patients with various stages of AD.

RESULTS

In Experiment I, the line bisection errors (LBEs) of AD subjects, but not of the controls, were markedly influenced by both background and within line stripe motions, deviations occurring in the same direction of movement. In Experiment II, LBEs also occurred in the same direction as background movement and increased with dementia severity.

CONCLUSIONS

These results demonstrate that patients with Alzheimer disease are spatially distracted by moving stimuli.

Podocyte biology in diabetic nephropathy

Glomerular visceral epithelial cells, namely podocytes, are highly specialized cells and give rise to primary processes, secondary processes, and finally foot processes. The foot processes of neighboring podocytes interdigitate, leaving between them filtration slits. These are bridged by an extracellular substance, known as the slit diaphragm, which plays a major role in establishing size-selective barrier to protein loss. Furthermore, podocytes are known to synthesize matrix molecules to the glomerular basement membrane (GBM), including type IV collagen, laminin, entactin, and agrin. Because diabetic nephropathy is clinically characterized by proteinuria and pathologically by glomerular hypertrophy and GBM thickening with foot process effacement, podocytes have been the focus in the field of research on diabetic nephropathy. As a result, many investigations have demonstrated that the diabetic milieu per se, hemodynamic changes, and local growth factors such as transforming growth factor-beta and angiotensin II, which are considered mediators in the pathogenesis of diabetic nephropathy, induce directly and/or indirectly hypertrophy, apoptosis, and structural changes, and increase type IV collagen synthesis in podocytes. This review explores some of the structural and functional changes of podocytes under diabetic conditions and their role in the development and progression of diabetic nephropathy.

Bowtie and upbeat nystagmus evolving into hemi-seesaw nystagmus in medial medullary infarction: Possible anatomic mechanisms

A 20-year-old man with bilateral medial medullary infarction showed transition of bowtie and upbeat nystagmus into hemi-seesaw nystagmus. Follow-up MRI revealed near complete resolution of the right medullary lesion. This transition of nystagmus suggests that the upbeat nystagmus was generated by bilateral lesions in the ascending pathways from both anterior semicircular canals (SCC), and that the hemi-seesaw nystagmus was caused by damage to the pathway from the left anterior SCC.

A new antioxidant monoterpene glycoside, alpha-benzoyloxypaeoniflorin from Paeonia suffruticosa

Alpha-benzoyloxypaeoniflorin (1), a new antioxidant monoterpene alpha-glycoside anomer was isolated from Paeonia suffruticosa along with known compounds, beta-benzoyloxypaeoniflorin (2), paeonolide, paeoniflorin and mudanpioside H. The structure of 1 has been determined by comparing spectral data with those of beta-benzoyloxypaeoniflorin (2). Compound 1 exhibited moderately potent radical scavenging activity on DPPH radical.

Production of indoxyl derivatives in indole-supplemented tissue cultures of Polygonum tinctorium

A red pigment produced in the suspension, root and, shoot cultures of Polygonum tinctorium Ait. (Polygonaceae) upon feeding of indole was identified as indirubin by comparison with the authentic compound obtained from the leaves of the plant. Indole-5-D was specifically incorporated into the pigment to form indirubin-5,5'-D(2) when fed to the cultures. Tryptophan feeding did not cause the accumulation of the pigment. The dilution of the fed indole with the endogeneous indole was about zero, ten, and thirty-five percent for the suspension, root, and shoot cultures, respectively. The feeding of indole to the suspension and root cultures suppressed the biosynthesis of indigo thus resulting in the production of indirubin. However, the fed indole was equally well incorporated into indigo and indirubin in the shoot culture.

Do N-methyl-D-aspartate antagonists have disproportionately greater effects on brain swelling than on ischemic damage in focal cerebral infarction?

Using a frozen section technique, we have assessed the effects of N-methyl-D-aspartate (NMDA) antagonist upon brain swelling caused by ischemic brain edema in a rat model of focal cerebral infarction. Although pretreatment with the competitive NMDA antagonist, D-CPPene or the noncompetitive NMDA antagonist, CNS 1102 reduced both the volumes of infarction and ischemic edema in the cerebral hemisphere, mean reduction in brain edema was proportionately similar to decrease in infarct volume in the same animals (correlation coefficient, r = 0.82, p < 0.001). There was, therefore, no evidence of disproportionately greater effects with NMDA antagonist upon brain edema.

Influence of fat and emulsifiers on the efficacy of nisin in inhibiting Listeria monocytogenes in fluid milk

The recent FDA affirmation of nisin, an antimicrobial peptide, as a GRAS (generally recognized as safe) additive in pasteurized cheese spreads has renewed interest in its potential application in US dairy products. Fluid milks were prepared with varying concentrations of milk fat (0 to 12.9%) and of nisin (0 to 50 U/ml). Biological activity assays using a sensitive indicator microorganism in a well diffusion system indicated that initial nisin activity (50 U/ml) decreased by about 33% when it was added to skim milk and by more than 88% when added to milk containing 12.9% fat. Nisin activity decreased by ca. 50% in milk containing 1.29% fat. Milks containing 0, 10, or 50 U/ml of nisin and varying fat percentages were challenged with approximately log10 7 to 7.5 cfu/ml of log phase Listeria monocytogenes Scott A or Jalisco. At 2 h after inoculation, the viable count of L. monocytogenes Scott A decreased to log10 .30 cfu/ml in skim milk with 50 U/ml of nisin, decreased to log10 2.90 cfu/ml in skim milk with 10 U/ml of nisin, and increased slightly (log10 7.8 cfu/ml) in skim milk without nisin. In half-and-half (12.9% milk fat), nisin was far less effective in inhibiting Listeria with populations decreasing to log10 6.57 cfu/ml for 10 U/ml of nisin and log10 5.87 cfu/ml for 50 U/ml. Similar results were obtained with L. monocytogenes Jalisco. The nonionic emulsifier, Tween 80, partially counteracted decreases of nisin activity in milks, whereas the anionic emulsifier, lecithin, had no effect. Addition of Tween 80 significantly increased the activity of nisin against L. monocytogenes in milk regardless of fat content.

Controlling Wine Malolactic Fermentation with Nisin and Nisin-Resistant Strains of Leuconostoc oenos

The polypeptide nisin (100 U/ml) prevented malolactic fermentation in wines by indigenous or intentionally added lactic acid bacteria. Nisin (100 U/ml)-resistant mutants of Leuconostoc oenos were obtained and used with nisin in wine to carry out a pure-culture malolactic fermentation in the presence or absence of other lactic acid bacteria. Nisin degradation by mutants was not observed, and residual nisin was detectable in wines 4 months after it was added. Results indicated that nisin or nisin with resistant bacterial starter cultures can be used to control malolactic fermentation in wines.