Clinical characteristics and intracranial arterial lesions of non-young adult ischemic stroke patients with RNF213 p.R4810K variant.

BACKGROUND: Although RNF213 p.R4810K, a genetic susceptibility variant for moyamoya disease (MMD), is associated with intracranial artery stenosis/occlusion (ICASO), the impact of this variant on ischemic stroke patients in non-young adults is unclear. We aimed to determine the characteristics of non-young adult stroke patients with RNF213 p.R4810K. METHODS: We retrospectively identified acute ischemic stroke patients ≥50 years who were admitted to our hospital and underwent intracranial vascular imaging. We reviewed the patients with RNF213 p.R4810K and compared stroke characteristics and the frequency and location of ICASO between patients with and without the variant. RESULTS: Among 341 patients, RNF213 p.R4810K was identified in 7 patients (2.1%). Five of the 7 patients with the variant (71%) had multiple ICASO without any finding of MMD and remaining 2 patients had no ICASO. The presumed etiologies of ICASO were atherosclerosis in 3 cases, vasculitis in 1, and undetermined vasculopathy in 1. ICASO in the anterior circulation was more common in patients with the variant than in those without (71% vs. 25%). The internal carotid artery, the M1 segment of the middle cerebral artery, the A1 segment of the anterior cerebral artery, and the P1 segment of the posterior cerebral artery, which were the most frequently affected arteries in MMD, were more often affected in the variant group. CONCLUSIONS: Non-young adult stroke patients with RNF213 p.R4810K are more likely to have ICASO in arterial segments commonly affected in MMD. The etiology of their ICASO exhibited diverse mechanisms, possibly depending on vascular risk and other environmental factors.

[Brain infarction and cerebral venous thrombosis in paroxysmal nocturnal hemoglobinuria: case report].

A 65-year-old woman with a six-year history of paroxysmal nocturnal hemoglobinuria (PNH) was admitted due to weakness in the right leg following a seven-day history of fever and upper respiratory infection. MRI revealed several high-intensity areas in bilateral frontal lobe cortices and the left cerebellum on diffusion-weighted imaging, and signal hypointensity along the course of the cortical vein in the left frontal lobe on T2*-weighted imaging. We diagnosed cerebral venous thrombosis and brain infarction, and commenced heparin infusion. She developed right-sided dens hemiparesis on hospital day 6, when brain CT showed subcortical hemorrhage in the left frontal lobe. Despite eculizumab administration and decompressive craniectomy for hematoma, she died on hospital day 26. Thrombosis in PNH has been recognized as a life-threating complication, and intensive treatment including emergent administration of eculizumab is warranted if this situation arises.

Regioselective aromatic substitution reactions of cyclometalated Ir(III) complexes: synthesis and photochemical properties of substituted Ir(III) complexes that exhibit blue, green, and red color luminescence emission.

In this manuscript, the regioselective halogenation, nitration, formylation, and acylation of Ir(tpy)(3) and Ir(ppy)(3) (tpy = 2-(4'-tolyl)pyridine and ppy = 2-phenylpyridine) and the subsequent conversions are described. During attempted bromination of the three methyl groups in fac-Ir(tpy)(3) using N-bromosuccinimide (NBS) and benzoyl peroxide (BPO), three protons at the 5'-position (p-position with respect to the C-Ir bond) of phenyl rings in tpy units were substituted by Br, as confirmed by (1)H NMR spectra, mass spectra, and X-ray crystal structure analysis. It is suggested that such substitution reactions of Ir complexes proceed via an ionic mechanism rather than a radical mechanism. UV-vis and luminescence spectra of the substituted Ir(III) complexes are reported. The introduction of electron-withdrawing groups such as CN and CHO groups at the 5'-position of tpy induces a blue shift of luminescence emission to about 480 nm, and the introduction of electron-donating groups such as an amino group results in a red shift to about 600 nm. A reversible change of emission for the 5'-amino derivative of Ir(tpy)(3), Ir(atpy)(3), between red and green occurs upon protonation and deprotonation.

Attack Interval Is the Key to the Likely Pathogenesis of Multiple Transient Ischemic Attacks.

INTRODUCTION: The aim of this study was to test the hypothesis that the attack interval of multiple transient ischemic attacks (TIAs) is correlated with the underlying pathogenesis of ischemia. METHODS: Patients with multiple TIAs, defined as 2 or more motor deficits within 7 days, were studied. The attack interval between the last 2 episodes was classified into 3 groups: 2 episodes within an hour (Hour group), over hours within a day (Day group), and over days within a week (Week group). Patients with a lacunar syndrome, no cortical lesions, and no embolic sources were recognized as having a small vessel disease (SVD) etiology for their multiple events. RESULTS: Of 312 TIA patients admitted over a 9-year period, 50 (37 males, 13 females, mean 67.6 years) had multiple TIAs. Twelve patients were classified as being within the Hour group, 23 within the Day group, and 15 within the Week group. Lacunar syndromes were observed in 30 (75%, 35%, and 67%), embolic sources were detected in 28 (25%, 65%, and 67%), and a high signal lesion on diffusion-weighted imaging was depicted in 30 (75%, 48%, and 67%) patients (18 cortical, 11 subcortical, and one cerebellar). Patients in the Hour group had a significantly higher prevalence of SVD etiology (75%) than those in the Day and Week groups (30%, p = 0.0165; 27%, p = 0.0213, respectively). Four patients had a subsequent stroke within 7 days. CONCLUSION: Attack intervals of multiple TIAs may be correlated with the underlying pathogenesis of ischemia. Two motor deficits within an hour are more likely to suggest a SVD etiology.

RNF213 p.R4810K (c.14429G > A) Variant Determines Anatomical Variations of the Circle of Willis in Cerebrovascular Disease.

INTRODUCTION: Dysregulation of the RING finger protein 213 (RNF213) gene impairs vascular formation in experimental animal models. In addition, vascular abnormalities in the circle of Willis are associated with cerebrovascular disease. Here, we evaluated the relationship between the East Asian founder variant RNF213 p.R4810K and consequent anatomical variations in the circle of Willis in cerebrovascular disease. PATIENTS AND METHODS: The present study is an observational cross-sectional study. It included patients with acute anterior circulation non-cardioembolic stroke admitted to our institution within 7 days of symptom onset or last-known-well from 2011 to 2019, and those who participated in the National Cerebral and Cardiovascular Center Biobank. We compared anatomical variations of the vessels constituting the circle of Willis between RNF213 p.R4810K (c.14429G > A) variant carriers and non-carriers using magnetic resonance angiography and assessed the association between the variants and the presence of the vessels constituting the circle of Willis. Patients with moyamoya disease were excluded. RESULTS: Four hundred eighty-one patients [146 women (30%); median age 70 years; median baseline National Institutes of Health Stroke Scale score 5] were analyzed. The RNF213 p.R4810K variant carriers (n = 25) were more likely to have both posterior communicating arteries (PComAs) than the variant non-carriers (n = 456) (56% vs. 13%, P < 0.01). Furthermore, variant carriers were less likely to have an anterior communicating artery (AComA) than non-carriers (68% vs. 84%, P = 0.04). In a multivariate logistic regression analysis, the association of RNF213 p.R4810K variant carriers with the presence of both PComAs and the absence of AComA remained significant. CONCLUSION: Our findings suggest that the RNF213 p.R4810K variant is an important factor in determining anatomical variations in the circle of Willis.

Late recovery from unconsciousness in a patient with severe posterior reversible encephalopathy syndrome.

This study describes a patient case presenting with severe posterior reversible encephalopathy syndrome (PRES) who needed 3 months to recover impaired consciousness. We discuss the protracted time course needed to deal with severe PRES cases. Positive prognoses can emerge from these situations if treatment is prompt and precise.

[Vertebrobasilar territory embolisms due to the ununited fracture of the right clavicle from 35 years ago].

A 61-year-old man, with a history of right clavicular fracture 35 years prior, visited our hospital due to the sudden onset of vertigo and tinnitus following weakness and numbness in his left arm and leg. He also had a 6-month history of right arm pain with overuse. Brain MRI showed acute brain infarcts in the right posterior cerebral artery territory. Intravenous alteplase was administered 188 minutes after onset. Although heparin infusion was commenced on day 2, he had vertigo again on day 9, and MRI showed a recurrent brain infarct in the right posterior inferior cerebellar artery territory. Ultrasound examination revealed occlusion of his right subclavian artery beneath the old right clavicular fracture as well as mobile thrombus in the proximal portion of the right subclavian artery. We speculated that a pseudarthrosis at the site of the old right clavicular fracture had repetitively pressed the right subclavian artery. Subsequently, we considered thrombi, which had developed in the proximal portion of the right subclavian artery, migrated into the right vertebral artery, causing recurrent emboli in the vertebrobasilar artery territory.

[Safety of Dual Antiplatelet Therapy with Argatroban in Patients with Acute Ischemic Stroke].

To prevent early neurological worsening or recurrence in stroke patients with intracranial arterial stenosis or branch atheromatous disease, aggressive antithrombotic therapy, such as dual antiplatelet therapy (DAPT) with or without anticoagulant therapy, is warranted. Such an aggressive antithrombotic therapy, however, may increase the bleeding risk. We studied the risks of DAPT with the anticoagulant argatroban in patients with acute ischemic stroke or transient ischemic attack (TIA). Between October 2011 and September 2015, 341 patients with stroke or TIA, who received DAPT with argatroban within 48 hours after onset, were retrospectively studied. The endpoint was any bleeding event during hospitalization or 30 days after admission. Median duration of DAPT was 12 days, and 66% of the patients received intravenous heparin (median duration, 5 days) following argatroban. No symptomatic intracerebral hemorrhages were observed, while severe, moderate, and mild extracranial hemorrhages occured in one (0.3%), three (0.9%), and four (1.2%) patients, respectively. In conclusion, DAPT with argatroban can be safely administered to patients with acute ischemic stroke or TIA. (Received July 24, 2017; Accepted January 15, 2018; Published May 1, 2018).