Temporal and Spatial Clustering of Intracerebral Hemorrhage in Cerebral Amyloid Angiopathy.

OBJECTIVES: Cerebral amyloid angiopathy (CAA)-associated lobar intracerebral hemorrhage (ICH) has a high risk of recurrence, but the underlying mechanisms remain uncertain. We, therefore, aimed to characterize patterns of recurrent ICH. METHODS: We investigated early recurrent ICH (≥1 recurrent ICH event within 90 days of the index event) and ICH clusters (≥2 ICH events within 90 days at any time point) in 2 large cohorts of consecutive patients with first-ever ICH and available MRI. RESULTS: In 682 included patients (median age 68 years, 40.3% female, median follow-up time 4.1 years), 18 (2.6%) had an early recurrent ICH, which was associated with higher age and CAA. In patients with probable CAA, the risk of early recurrent ICH was increased 5-fold within the first 3 months compared with during months 4-12 (hazard ratio 5.41, 95% CI 2.18-13.4) while no significant difference was observed in patients without CAA. In patients with an ICH cluster, we observed spatial clustering (recurrent ICH within close proximity of index ICH in 63.0%) and a tendency for multiple sequential hemorrhages (≥3 ICH foci within 3 months in 44.4%). DISCUSSION: Our data provide evidence of both temporal and spatial clustering of ICH in CAA, suggesting a transient and localized active bleeding-prone process.

Comparative efficacy and safety among different doses of tenecteplase for acute ischemic stroke: A systematic review and network meta-analysis.

OBJECTIVES: Tenecteplase (TNK) is a promising alternative to alteplase (ALT) as the thrombolytic agent for acute ischemic stroke (AIS). However, its clinical outcomes in certain populations remain unclear. This study aimed to compare the efficacy and safety among different doses of TNK in AIS patients. METHODS: We searched PubMed, Scopus, Cochrane Central Register of Controlled Trials, and Embase for studies comparing at least one dose of TNK to another dose of TNK or ALT 0.90 mg/kg. We conducted Bayesian network meta-analyses to estimate the relative risks (RRs) and 95% credible intervals (CrIs) for all outcomes using ALT 0.90 mg/kg as the reference. The treatments were ranked according to their surface under the cumulative ranking (SUCRA) values. RESULTS: We included 11 trials from 16 publications comprising 5423 participants. There were no significant differences between any doses of TNK and ALT for reperfusion, 3-month modified Rankin Score (mRS) 0-1 (rank 1st: TNK 0.25 mg/kg; SUCRA = 0.68), mRS 0-2 (rank 1st: TNK 0.25 mg/kg; SUCRA = 0.86), mortality (rank 1st: TNK 0.25 mg/kg; SUCRA = 0.82), intracranial hemorrhage (ICH) (rank 1st: TNK 0.25 mg/kg; SUCRA = 0.88), symptomatic ICH (sICH) (rank 1st: TNK 0.10 mg/kg; SUCRA = 0.70), and parenchymal hematoma (rank 1st: TNK 0.10 mg/kg; SUCRA = 0.68). TNK 0.40 mg/kg had a significantly higher sICH rate compared to TNK 0.25 mg/kg (RR = 2.39, 95% CrI = 1.00-7.92). Among elderly patients, TNK 0.25 mg/kg had a significantly lower rate of sICH than ALT 0.9 mg/kg (RR = 3.0 × 10-13, 95% CrI = 3.4 × 10-40-0.07). CONCLUSIONS: TNK has efficacy and safety outcomes comparable to those of ALT. TNK 0.25 mg/kg may be the optimal dose of TNK for patients with AIS.

How calcineurin inhibitors affect cognition.

AIMS: With a focus on the discrepancy between preclinical and clinical findings, this review will gather comprehensive information about the effects of calcineurin inhibitors (CNI) on cognitive function and related brain pathology from in vitro, in vivo, and clinical studies. We also summarize the potential mechanisms that underlie the pathways related to CNI-induced cognitive impairment. METHODS: We systematically searched articles in PubMed using keywords 'calcineurin inhibitor*' and 'cognition' to identify related articles, which the final list pertaining to underlying mechanisms of CNI on cognition. RESULTS: Several studies have reported an association between calcineurin and the neuropathology of Alzheimer's disease (AD). AD is the most common neurocognitive disorder associated with amyloid plaques and neurofibrillary tangles in the brain, leading to cognitive impairment. CNI, including tacrolimus and cyclosporin A, are commonly prescribed for patients with transplantation of solid organs such as kidney, liver, or heart, those drugs are currently being used as long-term immunosuppressive therapy. Although preclinical models emphasize the favorable effects of CNI on the restoration of brain pathology due to the impacts of calcineurin on the alleviation of amyloid-beta deposition and tau hyperphosphorylation, or rescuing synaptic and mitochondrial functions, treatment-related neurotoxicity, resulting in cognitive dysfunctions has been observed in clinical settings of patients who received CNI. CONCLUSION: Inconsistent results of CNI on cognition from clinical studies have been observed due to impairment of the blood-brain barrier, neuroinflammation mediated by reactive oxygen species, and alteration in mitochondrial fission, and extended research is required to confirm its promising use in cognitive impairment.

Possible Roles of Extracellular Vesicles in the Pathogenesis and Interventions of Immune-Mediated Central Demyelinating Diseases.

Multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) are two of the most devastating immune-mediated central demyelinating disorders. NMOSD was once considered as a variant of MS until the discovery of an antibody specific to the condition. Despite both MS and NMOSD being considered central demyelinating disorders, their pathogenesis and clinical manifestations are distinct, however the exact mechanisms associated with each disease remain unclear. Extracellular vesicles (EVs) are nano-sized vesicles originating in various cells which serve as intercellular communicators. There is a large body of evidence to show the possible roles of EVs in the pathogenesis of several diseases, including the immune-mediated central demyelinating disorders. Various types of EVs are found across disease stages and could potentially be used as a surrogate marker, as well as acting by carrying a cargo of biochemical molecules. The possibility for EVs to be used as a next-generation targeted treatment for the immune-mediated central demyelinating disorders has been investigated. The aim of this review was to comprehensively identify, compile and discuss key findings from in vitro, in vivo and clinical studies. A summary of all findings shows that: 1) the EV profiles of MS and NMOSD differ from those of healthy individuals, 2) the use of EV markers as liquid biopsy diagnostic tools appears to be promising biomarkers for both MS and NMOSD, and 3) EVs are being studied as a potential targeted therapy for MS and NMOSD. Any controversial findings are also discussed in this review.