Publications by authors named "Nobukazu Miyamoto"

Background: Inflammation promotes atherogenesis. Randomized controlled trials of anti-inflammatory therapies for prevention after stroke have not yet demonstrated clear benefit. IL-6 (interleukin-6) and hsCRP (high-sensitivity C-reactive protein) are independently associated with major adverse cardiovascular events poststroke and may guide patient selection in future randomized controlled trials.

View Article and Find Full Text PDF

Purpose: A high-risk patent foramen ovale (PFO) could be the cause of cryptogenic stroke, and an atrial septal aneurysm (ASA) increases the risk of stroke recurrence in cryptogenic stroke patients with a patent foramen ovale (PFO). Factors related to stroke recurrence according to PFO characteristics have not been fully evaluated.

Methods: Data from a multicenter, observational registry of ischemic stroke patients undergoing transesophageal echocardiography were used for this study.

View Article and Find Full Text PDF

Background And Aims: Compared to small vessel occlusion (SVO) patients, branch atheromatous disease (BAD) patients are more likely to develop early neurological deterioration (END). Stroke patients with END have a poor prognosis. Initial clinical features/radiological findings are often insufficient to distinguish between BAD and SVO; therefore, they may not detect END.

View Article and Find Full Text PDF

Introduction: Inflammation is an emerging target for secondary prevention after stroke and randomised trials of anti-inflammatory therapies are ongoing. Fibrinogen, a putative pro-inflammatory marker, is associated with first stroke, but its association with major adverse cardiovascular events (MACE) after stroke is unclear.

Materials And Methods: We did a systematic review investigating the association between fibrinogen and post-stroke vascular recurrence.

View Article and Find Full Text PDF

Background: Covert atrial fibrillation (AF) is a major cause of cryptogenic stroke. This study investigated whether a dose-dependent relationship exists between the frequency of premature atrial contractions (PACs) and AF detection in patients with cryptogenic stroke using an insertable cardiac monitor (ICM).

Methods: We enrolled consecutive patients with cryptogenic stroke who underwent ICM implantation between October 2016 and September 2020 at 8 stroke centers in Japan.

View Article and Find Full Text PDF

Background: Atrial fibrillation (AF) is known to be a strong risk factor for stroke. However, the risk of stroke recurrence in patients with cryptogenic stroke with AF detected after stroke by an insertable cardiac monitor (ICM) is not well known. We sought to evaluate the risk of ischemic stroke recurrence in patients with cryptogenic stroke with and without ICM-detected AF.

View Article and Find Full Text PDF

Background And Objectives: Anti-inflammatory therapies reduce major adverse cardiovascular events (MACE) in coronary artery disease but remain unproven after stroke. Establishing the subtype-specific association between inflammatory markers and recurrence risk is essential for optimal selection of patients in randomized trials (RCTs) of anti-inflammatory therapies for secondary stroke prevention.

Methods: Using individual participant data (IPD) identified from a systematic review, we analyzed the association between high-sensitivity C-reactive protein, interleukin-6 (IL-6), and vascular recurrence after ischemic stroke or transient ischemic attack.

View Article and Find Full Text PDF

Background And Aims: It is important to diagnose cerebral infarction at an early stage and select an appropriate treatment method. The number of stroke-trained physicians is unevenly distributed; thus, a shortage of specialists is a major problem in some regions. In this retrospective design study, we tested whether an artificial intelligence (AI) we built using computer-aided detection/diagnosis may help medical physicians to classify stroke for the appropriate treatment.

View Article and Find Full Text PDF

There are no effective treatments for post-stroke glial scar formation, which inhibits axonal outgrowth and functional recovery after stroke. We investigated whether astrocytic extracellular vesicles (AEVs) regulated by microglia modulate glial scars and improve stroke recovery. We found that peri-infarct glial scars comprised reactive astrocytes with proliferating C3d and decreased S100A10 expression in chronic stroke.

View Article and Find Full Text PDF

Background: An insertable cardiac monitor (ICM) and transesophageal echocardiography (TEE) are useful for investigating potential embolic sources in cryptogenic stroke, of which atrial fibrillation (AF) is a critical risk factor for stroke recurrence. The association of left atrial appendage flow velocity (LAA-FV) on TEE with ICM-detected AF is yet to be elucidated.

Methods: CRYPTON-ICM (CRYPTOgenic stroke evaluation in Nippon using ICM) is a multicenter registry of cryptogenic stroke with ICM implantation, and patients whose LAA-FV was evaluated on TEE were enrolled.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates how diet-induced obesity affects cognitive decline and white matter lesions (WMLs) linked to brain ischemia, focusing on neuroinflammation triggered by lipopolysaccharides (LPS) through toll-like receptor (TLR) 4.
  • Wild-type and TLR4-knockout mice were fed either a high-fat or low-fat diet, then subjected to carotid artery narrowing to assess changes in inflammation and cognitive function.
  • Results showed that diet-induced obesity exacerbated cognitive impairment and WML severity in wild-type mice, while TLR4-KO mice did not exhibit these effects, suggesting inflammation through LPS-TLR4 signaling plays a significant role in obesity-related cognitive issues.
View Article and Find Full Text PDF

Background: Anti-inflammatory therapies reduce recurrent vascular events in coronary disease. Existing studies have reported highly conflicting findings for the association of blood inflammatory markers with vascular recurrence after stroke leading to uncertainty about the potential of anti-inflammatory therapies after stroke and no consensus about the utility of measurement of inflammatory markers in current guidelines.

Methods: We investigated the association between hsCRP (high-sensitivity C-reactive protein), IL-6 (interluekin-6), and recurrent major adverse cardiovascular events (MACE), and stroke from individual participant data from 8420 patients with ischemic stroke/transient ischemic attack from 10 prospective studies.

View Article and Find Full Text PDF

Background: Embolic stroke of undetermined source (ESUS) encompasses diverse embologenic mechanisms, which transesophageal echocardiography (TEE) is critical to detect. Specific markers related to each embolic source in ESUS is not fully studied. We focused on D-dimer levels, and explored the association of D-dimer with potential embolic sources (PES) identified on TEE in ESUS.

View Article and Find Full Text PDF

Background And Aims: Platelets play an important role in homeostasis however, they have also been associated with increased mortality after myocardial infarction. In the present study, we investigated whether platelet count is associated with differences in the short-term prognosis at the time of hospital discharge and early neurological deterioration in ischemic stroke patients.

Methods: Patients with ischemic stroke were enrolled from among 661 cerebrovascular disease patients admitted between January 2018 and December 2020.

View Article and Find Full Text PDF

Polycythemia vera (PV) is one of the myeloproliferative neoplasms and has higher frequency of the V617F mutation. Hemorrhagic stroke is rare in PV, and myelofibrosis is secondary to PV. A 76-year-old Japanese man was diagnosed as PV with the V617F mutation at the age of 63 years.

View Article and Find Full Text PDF
Article Synopsis
  • - The study looked at how plasma D-dimer levels, which indicate hypercoagulability, affect short-term outcomes for cancer patients who have had an ischemic stroke.
  • - Out of 282 patients analyzed, nearly 48% experienced poor outcomes, while 12.4% died within 30 days, and higher post-treatment D-dimer levels were linked to these negative outcomes.
  • - The research suggests that administering anticoagulants, like heparin, can lower D-dimer levels post-treatment, potentially improving the short-term recovery of these patients without increasing bleeding risks.
View Article and Find Full Text PDF
Article Synopsis
  • Creutzfeldt-Jakob disease (CJD) is a fatal brain disease caused by prions, and while dizziness is an uncommon early symptom, it can lead patients to visit the wrong medical department.
  • A 56-year-old woman with CJD presented with dizziness and exhibited specific eye movement abnormalities, prompting further investigation.
  • The case highlights the importance of considering CJD in patients with dizziness and unusual eye movements, as early diagnosis can prevent serious complications.
View Article and Find Full Text PDF

Background: The COVID-19 pandemic has forced lockdowns and declarations of states of emergency, resulting in marked changes to daily life such as dietary habits in many countries. Though serum omega-3 polyunsaturated fatty acids levels have been shown to be useful markers for recurrent vascular events or worse prognosis in cardiovascular diseases and ischemic stroke, the relationship between serum omega-3 PUFA levels and the occurrence of intracerebral hemorrhage has essentially been unknown. We explored the association of serum omega-3 polyunsaturated fatty acids with intracerebral hemorrhage during the COVID-19 pandemic.

View Article and Find Full Text PDF

Although l-carnitine alleviated white-matter lesions in an experimental study, the treatment effects of l-carnitine on white-matter microstructural damage and cognitive decline in hemodialysis patients are unknown. Using novel diffusion magnetic resonance imaging (dMRI) techniques, white-matter microstructural changes together with cognitive decline in hemodialysis patients and the effects of l-carnitine on such disorders were investigated. Fourteen hemodialysis patients underwent dMRI and laboratory and neuropsychological tests, which were compared across seven patients each in two groups according to duration of l-carnitine treatment: (1) no or short-term l-carnitine treatment (NSTLC), and (2) long-term l-carnitine treatment (LTLC).

View Article and Find Full Text PDF
Article Synopsis
  • The research involved MR1 knockout mice and wild-type mice undergoing a transient middle cerebral artery occlusion (tMCAO), revealing that MR1 mice showed reduced brain damage and inflammation markers.
  • Results indicated that regulating MAIT cells could be a promising approach for neuroprotection in acute ischemic stroke, as their infiltration in the brain was reduced, correlating with improved neurological outcomes.
View Article and Find Full Text PDF

Duplication and accessory of the middle cerebral artery (MCA) constitute a rare congenital variation. MCA anomalies are found at a lesser frequency than the vascular anomalies of the other major intracranial arteries. Duplicated/accessory MCA was usually noted incidentally with subarachnoid hemorrhage, due to resulted aneurysmal formation.

View Article and Find Full Text PDF

Pioglitazone (PGZ), a PPARγ agonist, has been used for diabetic patients as an insulin-sensitizing agent. Recent studies have demonstrated that PGZ increases adiponectin (APN) levels and provides vascular protection in ischemic conditions. This study was designed to assess the neuroprotective effects of PGZ against cerebral ischemia-reperfusion injury via an APN-related mechanism.

View Article and Find Full Text PDF

A-kinase anchor protein 12 (AKAP12) is a scaffolding protein that associates with intracellular molecules to regulate multiple signal transductions. Although the roles of AKAP12 in the central nervous system are still relatively understudied, it was previously shown that AKAP12 regulates blood-retinal barrier formation. In this study, we asked whether AKAP12 also supports the function and integrity of the blood-brain barrier (BBB).

View Article and Find Full Text PDF

Introduction: Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by thromboembolic events, including ischemic stroke or complications in pregnancy, and the presence of antiphospholipid antibodies. Cervical artery dissection (CAD) is not an uncommon cause of stroke in young adults. The concomitant presence of APS and CAD is extremely rare.

View Article and Find Full Text PDF