Efficacy and Safety of Cilostazol in Mild Cognitive Impairment: A Randomized Clinical Trial.

Importance: Recent evidence indicates the efficacy of ß-amyloid immunotherapy for the treatment of Alzheimer disease, highlighting the need to promote ß-amyloid removal from the brain. Cilostazol, a selective type 3 phosphodiesterase inhibitor, promotes such clearance by facilitating intramural periarterial drainage. Objective: To determine the safety and efficacy of cilostazol in mild cognitive impairment. Design, Setting, and Participants: The COMCID trial (A Trial of Cilostazol for Prevention of Conversion from Mild Cognitive Impairment to Dementia) was an investigator-initiated, double-blind, phase 2 randomized clinical trial. Adult participants were registered between May 25, 2015, and March 31, 2018, and received placebo or cilostazol for up to 96 weeks. Participants were treated in the National Cerebral and Cardiovascular Center and 14 other regional core hospitals in Japan. Patients with mild cognitive impairment with Mini-Mental State Examination (MMSE) scores of 22 to 28 points (on a scale of 0 to 30, with lower scores indicating greater cognitive impairment) and Clinical Dementia Rating scores of 0.5 points (on a scale of 0, 0.5, 1, 2, and 3, with higher scores indicating more severe dementia) were enrolled. The data were analyzed from May 1, 2020, to December 1, 2020. Interventions: The participants were treated with placebo, 1 tablet twice daily, or cilostazol, 50 mg twice daily, for up to 96 weeks. Main Outcomes and Measures: The primary end point was the change in the total MMSE score from baseline to the final observation. Safety analyses included all adverse events. Results: The full analysis set included 159 patients (66 [41.5%] male; mean [SD] age, 75.6 [5.2] years) who received placebo or cilostazol at least once. There was no statistically significant difference between the placebo and cilostazol groups for the primary outcome. The least-squares mean (SE) changes in the MMSE scores among patients receiving placebo were -0.1 (0.3) at the 24-week visit, -0.8 (0.3) at 48 weeks, -1.2 (0.4) at 72 weeks, and -1.3 (0.4) at 96 weeks. Among those receiving cilostazol, the least-squares mean (SE) changes in MMSE scores were -0.6 (0.3) at 24 weeks, -1.0 (0.3) at 48 weeks, -1.1 (0.4) at 72 weeks, and -1.8 (0.4) at 96 weeks. Two patients (2.5%) in the placebo group and 3 patients (3.8%) in the cilostazol group withdrew owing to adverse effects. There was 1 case of subdural hematoma in the cilostazol group, which may have been related to the cilostazol treatment; the patient was successfully treated surgically. Conclusions and Relevance: In this randomized clinical trial, cilostazol was well tolerated, although it did not prevent cognitive decline. The efficacy of cilostazol should be tested in future trials. Trial Registration: ClinicalTrials.gov Identifier: NCT02491268.

Gut dysbiosis is associated with aortic aneurysm formation and progression in Takayasu arteritis.

BACKGROUND: Takayasu arteritis (TAK) is an autoimmune large vessel vasculitis that affects the aorta and its major branches, eventually leading to the development of aortic aneurysm and vascular stenosis or occlusion. This retrospective and prospective study aimed to investigate whether the gut dysbiosis exists in patients with TAK and to identify specific gut microorganisms related to aortic aneurysm formation/progression in TAK. METHODS: We analysed the faecal microbiome of 76 patients with TAK and 56 healthy controls (HCs) using 16S ribosomal RNA sequencing. We examined the relationship between the composition of the gut microbiota and clinical parameters. RESULTS: The patients with TAK showed an altered gut microbiota with a higher abundance of oral-derived bacteria, such as Streptococcus and Campylobacter, regardless of the disease activity, than HCs. This increase was significantly associated with the administration of a proton pump inhibitor used for preventing gastric ulcers in patients treated with aspirin and glucocorticoids. Among patients taking a proton pump inhibitor, Campylobacter was more frequently detected in those who underwent vascular surgeries and endovascular therapy for aortic dilatation than in those who did not. Among the genus of Campylobacter, Campylobacter gracilis in the gut microbiome was significantly associated with clinical events related to aortic aneurysm formation/worsening in patients with TAK. In a prospective analysis, patients with a gut microbiome positive for Campylobacter were significantly more likely to require interventions for aortic dilatation than those who were negative for Campylobacter. Furthermore, patients with TAK who were positive for C. gracilis by polymerase chain reaction showed a tendency to have severe aortic aneurysms. CONCLUSIONS: A specific increase in oral-derived Campylobacter in the gut may be a novel predictor of aortic aneurysm formation/progression in patients with TAK.

[Role of Microbiota in Stroke Pathogenesis].

Stroke is the fourth leading cause of death and second leading cause of disability in Japan. Advances in DNA sequencing and bioinformatics have increased identification of host-microbial interactions in various systemic diseases. This review introduces the association between microbiome and stroke in human and animal models. The microbiota directly or indirectly interacts with vascular risk factors, including age, obesity, hypertension, diabetes mellitus, and hyperlipidemia. Moreover, emerging evidence suggests that the microbiome independently affects the progression of various stroke subtypes. Finally, we introduce our ongoing stroke microbiome research to perform comprehensive analyses and discover personalized therapeutic targets.

Harboring Cnm-expressing Streptococcus mutans in the oral cavity relates to both deep and lobar cerebral microbleeds.

BACKGROUND: Cerebral microbleeds (CMBs) influence long-term prognoses of stroke patients. Streptococcus mutans expressing the collagen-binding protein Cnm induces cerebrovascular inflammation, impairing blood brain barrier integrity and causing cerebral bleeding. Here, we examine the association of Cnm-positive S. mutans with CMBs. METHODS: Acute stroke patients were selected from a single-center registry database. Oral carriage of Cnm-positive or Cnm-negative S. mutans was determined using polymerase chain reaction assays. The associations of Cnm-positive S. mutans with CMB number and specifically the presence of >10 CMBs were examined using quasi-Poisson and logistic regression models, respectively. RESULTS: This study included 3154 stroke patients, of which 428 patients (median [interquartile range] age, 73.0 [63.0-81.0] years; 269 men [62.9%]) underwent oral bacterial examinations. In total, 326 patients harbored S. mutans. After excluding four patients without imaging data, we compared patients with Cnm-positive (n = 72) and Cnm-negative (n = 250) S. mutans. Harboring Cnm-positive S. mutans was independently associated with the presence of >10 CMBs (adjusted odds ratio 2.20 [1.18-4.10]) and higher numbers of deep and lobar CMBs (adjusted risk ratio 1.61 [1.14-2.27] for deep; 5.14 [2.78-9.51] for lobar), but not infratentorial CMBs, after adjusting for age, sex, hypertension, stroke type, National Institutes of Health Stroke Scale score, and cerebral amyloid angiopathy. CONCLUSIONS: Harboring Cnm-positive S. mutans was independently associated with a higher number of CMBs in deep and lobar locations. Reducing Cnm-positive S. mutans in the oral cavity may serve as a novel therapeutic approach for stroke.

Risk Assessment of Cnm-Positive Streptococcus mutans in Stroke Survivors (RAMESSES): Protocol for a Multicenter Prospective Cohort Study.

Introduction: The role of commensal microbiota in systemic diseases, including brain diseases, has attracted increasing attention. Oral infectious diseases, such as dental caries and periodontitis, are also involved in cerebrovascular diseases and cognitive impairment. Cerebral microbleeds (CMBs) and intracerebral hemorrhage due to small vessel disease (SVD), are presumably associated with a high risk of vascular cognitive impairment and stroke. We previously reported that Streptococcus mutans (S. mutans, the main pathogen of dental caries), harboring the cnm gene that encodes the collagen-binding protein Cnm, is associated with the development of hypertensive intracerebral hemorrhage and aggravation of CMBs. We also proposed a mechanism by which the circulating Cnm-expressing S. mutans causes intracerebral hemorrhage or CMBs; it binds to denuded basement membranes mainly composed of collagen IV through damaged tight junctions or it directly invades endothelial cells, resulting in blood-brain barrier injury. In November 2018, we initiated a multicenter, prospective cohort study (RAMESSES: Risk Assessment of Cnm-positive S. mutans in Stroke Survivors; UMIN Clinical Trials Registry: UMIN000045559) to explore the longitudinal association between Cnm-positive S. mutans and CMBs with comprehensive dental findings, which should determine the effect of Cnm-positive S. mutans in the oral cavity on the risk of CMB development and cognitive decline. Methods: Fifteen domestic institutes will be enlisted to enroll 230 patients who have at least one CMB in the deep brain area and develop a stroke within the past year. The prevalence of Cnm-positive S. mutans based on oral specimens and dental hygiene will be examined. The primary outcome is the number of newly developed deep CMBs. The secondary outcomes include the new development of lobar, subtentorial, or any type of CMBs; symptomatic intracerebral hemorrhage or ischemic stroke; changes in cognitive function or frailty; major bleeding; all-cause mortality; and antibody titers against periodontal pathogens. The observation period will be 2 years. Discussion: The 2-year longitudinal prospective cohort study is expected to establish the role of Cnm-positive S. mutans in SVD including CMBs and intracerebral hemorrhage from the perspective of the "brain-oral axis" and provide guidance for novel prophylactic strategies against Cnm-positive S. mutans-induced SVD.

Cerebral microbleeds in vascular dementia from clinical aspects to host-microbial interaction.

Vascular dementia is the second leading cause of dementia after Alzheimer's disease in the elderly population worldwide. Cerebral microbleeds (CMBs) are frequently observed in MRI of elderly subjects and considered as a possible surrogate marker. The number and location of CMBs reflect the severity of diseases and the underlying pathologies may involve cerebral amyloid angiopathy or hypertensive vasculopathy. Accumulating evidence demonstrated the clinicopathological discrepancies of CMBs, the clinical significance of CMBs associated with other MRI markers of cerebral small vessel disease, cognitive impairments, serum, and cerebrospinal fluid biomarkers. Moreover, emerging evidence has shown that genetic factors and gene-environmental interactions might shed light on the underlying etiologies of CMBs, focusing on blood-brain-barrier and inflammation. In this review, we introduce recent genetic and microbiome studies as a cutting-edge approach to figure out the etiology of CMBs through the "microbe-brain-oral axis" and "microbiome-brain-gut axis." Finally, we propose novel concepts, "microvascular matrisome" and "imbalanced proteostasis," which may provide better perspectives for elucidating the pathophysiology of CMBs and future development of therapeutics for vascular dementia using CMBs as a surrogate marker.

Oral Carriage of Streptococcus mutans Harboring the cnm Gene Relates to an Increased Incidence of Cerebral Microbleeds.

BACKGROUND AND PURPOSE: Cerebral microbleeds (CMB) are associated with stroke and cognitive impairment. We previously reported a high prevalence of CMB in people with Streptococcus mutans expressing Cnm, a collagen-binding protein in the oral cavity. S.mutans is a major pathogen responsible for dental caries. Repeated challenge with S.mutans harboring the cnm gene encoding Cnm induced cerebral bleeding in stroke-prone spontaneously hypertensive rats. The purpose of this longitudinal study is to examine the relationship of cnm-positive S.mutans to the development of CMB. METHODS: We retrospectively investigated patients with stroke receiving oral microbiological examination and head 3T magnetic resonance imaging evaluations twice in the period 2014 to 2019, allowing >180-day interval. Patients with cnm-positive S.mutans were compared with those without. Quasi-Poisson regression models were used to explore associations between cnm-positive S.mutans and the increase in number of CMB between the 2 magnetic resonance imaging scans. RESULTS: A total of 111 patients were identified; 21 (19%) with cnm-positive S.mutans and 90 (81%) without. Clinical history, including blood pressure and the use of antithrombotic agents, were comparable between the 2 groups. New CMB were more commonly observed in patients with cnm-positive S.mutans (52% versus 23%; P=0.008). The incidence of CMB was significantly higher in the group with cnm-positive S.mutans, especially in deep areas, (incidence rate ratios [95% CI], 5.1 [1.9-13.6] for CMB in any brain region; 15.0 [5.4-42.0] for deep CMB), which persisted after adjusting for age, sex, hypertension, and renal impairment (4.7 [1.8-11.9] for CMB in any brain region; 13.9 [4.3-44.5] for deep CMB). CONCLUSIONS: This study demonstrates that cnm-positive S.mutans is associated with an increased incidence of CMB. Treatment for cnm-positive S.mutans infection may be a novel microbiota-based therapeutic approach for stroke and cognitive impairment.

Microbiota in cerebrovascular disease: A key player and future therapeutic target.

Stroke is the second leading cause of death and a significant cause of disability worldwide. Recent advances in DNA sequencing, proteomics, metabolomics, and computational tools are dramatically increasing access to the identification of host-microbiota interactions in systemic diseases. In this review, we describe the accumulating evidence showing how human microbiota plays an essential role in cerebrovascular diseases. We introduce the symbiotic relationships between microbiota and the mucosal immune system, focusing on differences by anatomical sites. Microbiota directly or indirectly contributes to the pathogenesis of traditional vascular risk factors including age, obesity, diabetes mellitus, dyslipidemia, and hypertension. Moreover, recent studies proposed independent effects of the microbiome on the progression of various subtypes of stroke through direct microbial invasion, exotoxins, functional amyloids, inflammation, and microbe-derived metabolites. We propose the critical concept of gene-microbial interaction to elucidate the heterogeneity of stroke and provide possible therapeutic avenues. We suggest ways to resolve the vast inter-individual diversity of cerebrovascular disease and mechanisms for personalized prevention and treatment.

Field Assessment of Critical Stroke by Emergency Services for Acute Delivery to a Comprehensive Stroke Center: FACE2AD.

Patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) should be triaged to an endovascular-capable hospital by the emergency medical service (EMS). We designed a prehospital LVO prediction scale based on EMS assessments. In the derivation cohort, 1157 patients transferred to our hospital by the EMS because of suspected stroke within 24 h of onset were retrospectively examined. Factors associated with AIS due to LVO were identified based on the EMS assessment, and a prehospital scale identifying LVO was developed. The accuracy of this scale was validated in 502 consecutive patients who were transferred to 4 stroke centers, and its accuracy was compared with those of 4 previously reported scales. AIS due to LVO was diagnosed in 149 of 1157 patients (13%) in the derivation cohort. One point each was assigned for facial palsy, arm weakness, consciousness impairment (cannot say his/her name), atrial fibrillation, and diastolic blood pressure ≤ 85 mmHg, with two points for conjugate eye deviation (FACE2AD scale). In the derivation cohort, with the optimal cut-point of FACE2AD ≥ 3 determined by the area under the curve (AUC; 0.88; 95% confidence interval 0.87-0.90), sensitivity, specificity, positive predictive value, and negative predictive value for FACE2AD to predict LVO were 0.85, 0.80, 0.39, and 0.97, respectively. In the validation cohort, the FACE2AD scale had higher accuracy, with an AUC value of 0.84 for predicting LVO compared with the other scales (all p < 0.01). The FACE2AD scale is a simple, reliable tool for identifying AIS due to LVO by the EMS.

Relationship between Streptococcus mutans expressing Cnm in the oral cavity and non-alcoholic steatohepatitis: a pilot study.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a severe state of non-alcoholic fatty liver disease (NAFLD), which is pathologically characterised by steatosis, hepatocyte ballooning, and lobular inflammation. Host-microbial interaction has gained attention as one of the risk factors for NASH. Recently, cnm-gene positive Streptococcus mutans expressing cell surface collagen-binding protein, Cnm (cnm-positive S. mutans), was shown to aggravate NASH in model mice. Here, we assessed the detection rate of cnm-positive S. mutans in oral samples from patients with NASH among NAFLD. METHODS: This single hospital cohort study included 41 patients with NAFLD. NASH was diagnosed histologically or by clinical score. The prevalence of cnm-positive S. mutans, oral hygiene and blood tests, including liver enzymes, adipocytokines and inflammatory and fibrosis markers, were assessed in biopsy-proven or clinically suspected NASH among NAFLD. RESULTS: Prevalence of cnm-positive S. mutans was significantly higher in patients with NASH than patients without NASH (OR 3.8; 95% CI 1.02 to 15.5). The cnm-positive S. mutans was related to decreased numbers of naturally remaining teeth and increased type IV collagen 7S level (median (IQR) 10.0 (5.0-17.5) vs 20.0 (5.0-25.0), p=0.06; 5.1 (4.0-7.9) vs 4.4 (3.7-5.3), p=0.13, respectively). CONCLUSIONS: Prevalence of cnm-positive S. mutans in the oral cavity could be related to fibrosis of NASH among NAFLD.

Utility of Complementary Magnetic Resonance Plaque Imaging and Contrast-Enhanced Ultrasound to Detect Carotid Vulnerable Plaques.

Background We aimed to improve the assessment quality of plaque vulnerability with combined use of magnetic resonance imaging and contrast-enhanced ultrasound ( CEUS ). Methods and Results We prospectively enrolled 71 patients with internal carotid artery stenosis who underwent carotid endarterectomy and performed preoperative CEUS and magnetic resonance plaque imaging. We distinguished high-signal-intensity plaques ( HIP s) and non- HIP s based on magnetization-prepared rapid acquisition with gradient echo images. We graded them according to the CEUS contrast effect and compared the CEUS images with the carotid endarterectomy specimens. Among the 70 plaques, except 1 carotid endarterectomy tissue sample failure, 59 were classified as HIP s (43 symptomatic) and 11 were classified as non- HIP s (5 symptomatic). Although the magnetization-prepared rapid acquisition with gradient echo findings alone had no significant correlation with symptoms ( P=0.07), concomitant use of magnetization-prepared rapid acquisition with gradient echo and CEUS findings did show a significant correlation ( P<0.0001). CEUS showed that all 5 symptomatic non- HIP s had a high-contrast effect. These 5 plaques were histopathologically confirmed as vulnerable, with extensive neovascularization but only a small amount of intraplaque hemorrhage. Conclusions Complementary use of magnetic resonance imaging and CEUS to detect intraplaque hemorrhage and neovascularization in plaques can be useful for evaluating plaque vulnerability, consistent with the destabilization process associated with neovessel formation and subsequent intraplaque hemorrhage.

A dural metastatic small cell carcinoma of the gallbladder as the first manifestation: a case report.

BACKGROUND: A dural metastasis is one of the essential differential diagnoses of meningioma. In general, carcinomas of the breast and lung in females and prostate in males have been the most commonly reported primary lesions of dural metastases. However, dural metastasis of gallbladder carcinoma is extremely rare. Here, we report a unique case of a dural matter metastasis of gallbladder carcinoma as the first manifestation, which was autopsy-defined as small cell carcinoma. CASE PRESENTATION: A 78-year-old man came to our hospital complaining of left hemianopia. Brain computed tomography (CT) revealed a sizeable parasagittal dural-based extra-axial tumor. However, the findings for meningioma were atypical by magnetic resonance imaging, suggesting a meningioma mimic. A contrast-enhanced CT scan of the abdomen revealed a large gallbladder carcinoma. The patient opted for the best supportive care and died 2 months later. The post-mortem examination revealed small cell carcinoma in gallbladder carcinoma. Moreover, an immunologically similar carcinoma was detected in the dural metastasis. CONCLUSIONS: To the best of our knowledge, this is the first case of a dural metastasis of gallbladder small cell carcinoma. A systemic examination is essential for clinicians when atypical findings of meningioma are observed, suggesting a meningioma mimic. We present this rare case with a review of the literature.

Pathologic Findings of Symptomatic Carotid Artery Stenosis Several Decades after Radiation Therapy: A Case Report.

Improved long-term survival of malignancy has drawn increased attention to late cerebrovascular toxicity after neck radiotherapy. Recently, neck radiotherapy has been found as a significant risk factor of carotid artery stenosis and ischemic stroke; however, long-term adverse effects of radiation in large arteries remain unknown. Here, we described an autopsied case with recurrent ischemic stroke associated with ipsilateral carotid artery stenosis several decades after neck radiation therapy. Pathologically, there were intima-media fibrosis, endothelial cell loss, and decreased expression of thrombomodulin in irradiated carotid artery stenosis. Our findings support the hypothesis that long-term radiation-induced vascular injury in large arteries is morphologically different from atherosclerotic change. Furthermore, endothelial cell injury may promote fibrin thrombus formation through decreased expression of thrombomodulin, which may cause ischemic stroke associated with radiation-induced carotid artery stenosis.

[Progressive dysarthria and bilateral sensory disturbance in a case of bilateral ventrolateral pontine infarction].

A rare case of bilateral ventrolateral pontine infarction in a 70-year-old man who developed progressive dysarthria and bilateral sensory disturbance is reported with literature review. He had been diagnosed with hypertension, dyslipidemia, and impaired glucose tolerance 10 years earlier. Ten days before admission, he was aware of the difficulty in walking and speaking, which gradually worsened. On admission he showed bilateral thermal hypoalgesia of face and lower extremities, dysarthria, dysphagia, and ataxic gait. High resolution three-dimensional MRI revealed bilateral ventrolateral pontine infarction with a large atherosclerotic plaque in the ventral side of the basilar artery, which led to a diagnosis of atherothrombotic brain infarction. The atherosclerotic plaque in the basilar artery was thought to be responsible for simultaneous occlusion of the bilateral short circumflex arteries of the pons.

Takotsubo-like Myocardial Dysfunction in a Patient with Botulism.

Botulinum toxin A (BTXA) can disrupt the neuromuscular and autonomic functions. We herein report a case of autonomic system dysfunction that manifested as Takotsubo-like myocardial dysfunction in a patient with botulism. Takotsubo syndrome results in acute cardiac insufficiency, another fatal complication of botulism in addition to respiratory muscle paralysis, particularly in patients with cardiovascular disease.

Intracerebral hemorrhage and deep microbleeds associated with cnm-positive Streptococcus mutans; a hospital cohort study.

Oral infectious diseases are epidemiologically associated with stroke. We previously showed that oral Streptococcus mutans with the cnm gene encoding a collagen-binding Cnm protein induced intracerebral hemorrhage (ICH) experimentally and was also associated with cerebral microbleeds (CMBs) in our population-based cohort study. We therefore investigated the roles of cnm-positive Streptococcus mutans in this single hospital-based, observational study that enrolled 100 acute stroke subjects. The cnm gene in Streptococcus mutans isolated from saliva was screened using PCR techniques and its collagen-binding activities examined. CMBs were evaluated on T2* gradient-recalled echo MRI. One subject withdrew informed consent and 99 subjects (63 males) were analyzed, consisting of 67 subjects with ischemic stroke, 5 with transient ischemic attack, and 27 with ICH. Eleven cases showed Streptococcus mutans strains positive for cnm. The presence of cnm-positive Streptococcus mutans was significantly associated with ICH [OR vs. ischemic stroke, 4.5; 95% CI, 1.17-19.1] and increased number of deep CMBs [median (IQR), 3 (2-9) vs. 0 (0-1), p = 0.0002]. In subjects positive for Streptococcus mutans, collagen binding activity was positively correlated with the number of deep CMBs (R(2) = 0.405; p < 0.0001). These results provide further evidence for the key role of oral health in stroke.