Plasma biomarkers for predicting the development of dementia in a community-dwelling older Japanese population

AIM

To assess the association between plasma amyloid β (Aβ) 42/40, phosphorylated tau (p-τ)181, glial fibrillary acidic protein (GFAP), or neurofilament light chain (NfL) and the risk of dementia and to determine whether these plasma biomarkers could improve the ability to predict incident dementia in a general older population.

METHODS

A total of 1346 Japanese community-dwelling individuals aged ≥65 years without dementia were followed prospectively for 5.0 years. Plasma biomarkers were quantified using a Simoa HD-X analyzer. A Cox proportional hazards model was used to estimate the hazard ratios of each plasma biomarker level for the risk of dementia.

RESULTS

During the follow-up, 151 participants developed dementia, of whom 108 had Alzheimer disease (AD) and 43 non-Alzheimer dementia (non-AD). Lower plasma Aβ42/40 levels and higher plasma p-τ181 levels were significantly associated with developing AD but not non-AD, whereas significant associations were observed between higher plasma levels of GFAP and NfL and risk of both AD and non-AD (all P for trend <0.05). In addition, adding these four plasma biomarkers into a model consisting of the total score of the dementia risk model significantly improved the predictive ability for incident dementia.

CONCLUSION

Our findings suggest that plasma Aβ42/40 and p-τ181 are specific markers of AD, and plasma GFAP and NfL are potential biomarkers for all-cause dementia in the general Japanese older population. In addition, the measurement of these plasma biomarkers may be a useful and relatively low-invasive procedure for identifying individuals at high risk for developing dementia in clinical practice.

[The Roles of Aβ in Alzheimer's Disease: In Light of the Latest Findings]

The 'amyloid hypothesis', initially put forward in 1992, posits that amyloid β protein (Aβ) contributes to neurodegeneration through aberrant aggregation. In the process of this aberrant aggregation, Aβ forms oligomers, protofibrils, and mature fibrils, ultimately developing plaques. These mature fibrils and plaques were believed to be the culprits behind the neurotoxicity and neurodegeneration seen in Alzheimer's disease (AD). However, growing evidence in recent years has led to the 'Aβ oligomer hypothesis', which suggests that the intermediate forms of aggregates, such as oligomers and protofibrils, exhibit stronger neurotoxicity than the mature forms. Consequently, efforts have been made to develop anti-Aβ antibody drugs that specifically target these intermediate aggregates. Such interventions hold promise as disease-modifying treatments for AD.

Serum high-sensitivity C-reactive protein and dementia in a community-dwelling Japanese older population (JPSC-AD)

In recent years, the association between neuroinflammatory markers and dementia, especially Alzheimer's disease (AD), has attracted much attention. However, the evidence for the relationship between serum-hs-CRP and dementia including AD are inconsistent. Therefore, the relationships of serum high-sensitivity CRP (hs-CRP) with dementia including AD and with regions of interest of brain MRI were investigated. A total of 11,957 community residents aged 65 years or older were recruited in eight sites in Japan (JPSC-AD Study). After applying exclusion criteria, 10,085 participants who underwent blood tests and health-related examinations were analyzed. Then, serum hs-CRP levels were classified according to clinical cutoff values, and odds ratios for the presence of all-cause dementia and its subtypes were calculated for each serum hs-CRP level. In addition, the association between serum hs-CRP and brain volume regions of interest was also examined using analysis of covariance with data from 8614 individuals in the same cohort who underwent brain MRI. After multivariable adjustment, the odds ratios (ORs) for all-cause dementia were 1.04 (95% confidence interval [CI] 0.76-1.43), 1.68 (95%CI 1.08-2.61), and 1.51 (95%CI 1.08-2.11) for 1.0-1.9 mg/L, 2.0-2.9 mg/L, and ≥ 3.0 mg/L, respectively, compared to < 1.0 mg/L, and those for AD were 0.72 (95%CI 0.48-1.08), 1.76 (95%CI 1.08-2.89), and 1.61 (95%CI 1.11-2.35), for 1.0-1.9 mg/L, 2.0-2.9 mg/L, and ≥ 3.0 mg/L, respectively, compared to < 1.0 mg/L. Multivariable-adjusted ORs for all-cause dementia and for AD prevalence increased significantly with increasing serum hs-CRP levels (p for trend < 0.001 and p = 0.001, respectively). In addition, the multivariable-adjusted temporal cortex volume/estimated total intracranial volume ratio decreased significantly with increasing serum hs-CRP levels (< 1.0 mg/L 4.28%, 1.0-1.9 mg/L 4.27%, 2.0-2.9 mg/L 4.29%, ≥ 3.0 mg/L 4.21%; p for trend = 0.004). This study's results suggest that elevated serum hs-CRP levels are associated with greater risk of presence of dementia, especially AD, and of temporal cortex atrophy in a community-dwelling Japanese older population.

Brain atrophy in normal older adult links tooth loss and diet changes to future cognitive decline

Several studies have found associations between poor oral health, particularly tooth loss and cognitive decline. However, the specific brain regions affected by tooth loss and the probable causes remain unclear. We conducted a population-based longitudinal cohort study in Nakajima, Nanao City, Japan. Between 2016 and 2018, 2454 residents aged ≥60 participated, covering 92.9% of the local age demographics. This study used comprehensive approach by combining detailed dental examinations, dietary assessments, magnetic resonance imaging (MRI) analysis, and cognitive evaluations. Tooth loss, even in cognitively normal individuals, is associated with parahippocampal gyrus atrophy and increased WMH volume, both of which are characteristics of dementia. Tooth loss was associated with altered dietary patterns, notably a reduction in plant-based food intake and an increase in fatty, processed food intake. This study highlights a possible preventative pathway where oral health may play a significant role in preventing the early neuropathological shifts associated with dementia.

Late-Life High Blood Pressure and Enlarged Perivascular Spaces in the Putaminal Regions of Community-Dwelling Japanese Older Persons

BACKGROUND

Enlarged perivascular spaces (EPVS) of the brain may be involved in dementia, such as Alzheimer's disease and cerebral small vessel disease (CSVD). Hypertension has been reported to be a risk factor for dementia and CSVD, but the association between blood pressure (BP) and perivascular spaces is still unclear. The aim of this study was to determine the association between BP and EPVS volumes and to examine the interactions of relevant factors.

METHODS

A total of 9296 community-dwelling subjects aged ≥65 years participated in a brain magnetic resonance imaging and health status screening examination. Perivascular volume was measured using a software package based on deep learning that was developed in-house. The associations between BP and EPVS volumes were examined by analysis of covariance and multiple regression analysis.

RESULTS

Mean EPVS volumes increased significantly with rising systolic and diastolic BP levels (P for trend = .003, P for trend<.001, respectively). In addition, mean EPVS volumes increased significantly for every 1-mmHg-increment in systolic and diastolic BPs (both P values <.001). These significant associations were still observed in the sensitivity analysis after excluding subjects with dementia.

CONCLUSIONS

The present data suggest that higher systolic and diastolic BP levels are associated with greater EPVS volumes in cognitively normal older people.

Gender and age influence the association between gait speed and mild cognitive impairment in community-dwelling Japanese older adults: from the Japan Prospective Studies Collaboration for Ageing and Dementia (JPSC-AD)

BACKGROUND

Studies have shown that decreased gait speed is associated with impaired cognitive function. However, whether this association is equivalent across ages or genders in the older population remains unclear. Thus, we examined the association between mild cognitive impairment (MCI) and gait speed emphasising the influence of age and gender.

METHODS

Overall, 8233 Japanese participants aged ≥65 years were enrolled in this cross-sectional study between 2016 and 2018. After stratification by gender and age group, the participants' gait speeds were divided into quintiles, and the difference in MCI prevalence at each gait speed quintile was calculated. Logistic regression analyses were performed to assess the odds of MCI for each quintile and to assess the influence of age and gender.

RESULTS

Males had a consistently higher prevalence of MCI than females. The odds of MCI were increased as gait speed decreased. Logistic regression analyses revealed that in the multivariable-adjusted model 2, the odds ratios (95% confidence interval; CI) for MCI were 2.02 (1.47-2.76) for females and 1.75 (1.29-2.38) for males in the slowest gait speed quintiles compared to the fastest quintile. In the stratified analyses, only males showed an age-dependent increase in the associations between gait speed and MCI, while females exhibited comparable associations across age groups.

CONCLUSIONS

Reduced gait speed was associated with increased odds of MCI, and this association may vary according to gender and age. Therefore, gait speed could serve as a valuable screening tool for MCI, with gender- and age-dependent clinical implications.

Charcot-Marie-Tooth Disease with a Novel Variant in Gap Junction Protein Beta 1 Presenting with Visual Field Defects

Pathogenic variants in Gap Junction Protein Beta 1 (GJB1) cause X-linked Charcot-Marie-Tooth (CMT) disease type 1 (CMTX1), which is a common hereditary motor and sensory neuropathy. A 45-year-old man presented with progressive muscle weakness, atrophy, sensory disturbance of all limbs from childhood, and visual field defects in both eyes at 40 years old. A segregation analysis revealed a novel variant, c.173C>A (p.P58H), in the GJB1 gene. Patients with variants at codon 58 in GJB1 showed clinically varied phenotypes, ranging from demyelinating neuropathy to cerebellar ataxia. This patient may represent one of the various clinical phenotypes of GJB1 variants.

Evaluation of Liver Functionality after Liver Stereotactic Body Radiation Therapy (SBRT) Using Blood Tests and Imaging Examinations

PURPOSE/OBJECTIVE(S)

Several studies have shown that liver function can be evaluated after hepatic stereotactic body radiation therapy (SBRT) using galactosyl human serum albumin (GSA) liver scintigraphy and Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI). However, there are no reports investigating the relationship (including Chile-Pugh classification) between imaging and blood tests. Therefore, we investigated the changes that occur in the liver between before and after SBRT by combining imaging (GSA, computed tomography (CT), and MRI) with blood tests that assess total liver function (albumin-bilirubin (ALBI) grade, ICG-R15). We decided to find a method that could assess liver reserve capacity locally and globally MATERIALS/METHODS: Of the 23 patients who underwent hepatic SBRT, 12 patients underwent GSA, MRI, and ICG-R15 testing before treatment, 1 month after treatment, and 3 months after treatment. All patients underwent imaging studies and blood tests at the beginning of treatment, 1 month after treatment, and 3 months after treatment ended. The evaluation items were as follows: 1) changes over time in Child-Pugh classification, ICG-R15, and ALBI values before and after SBRT; 2) changes over time in GSA count and ICG; and 3) selection of the optimal sequence for recognizing radiation hepatitis on MRI.

RESULTS

The ICG values were 14.4 before RT, 17.1 after 1 month, and 17.6 after 3 months. ICG worsened after 1 month of treatment, but was similar after 3 months. ALBI values were -2.61 before RT, -2.67 after 1 month, and -2.71 after 3 months. ALBl worsened slightly over time.

CONCLUSION

Regarding the ICG-R15, there was an average worsening of 2.8 after 1 month of treatment compared with before SBRT, but only of 0.5 between 1 month and 3 months after SBRT. Therefore, evaluation using ICG-R15 after SBRT after 1 month alone may be sufficient.

Diffuse glioma-induced structural reorganization in close association with preexisting syntax-related networks

Glioma in the left frontal cortex has been reported to cause agrammatic comprehension and induce global functional connectivity alterations within the syntax-related networks. However, it remains unclear to what extent the structural reorganization is affected by preexisting syntax-related networks. We examined 28 patients with a diffuse glioma in the left hemisphere and 23 healthy participants. Syntactic abilities were assessed by a picture-sentence matching task with various sentence types. The lesion responsible for agrammatic comprehension was identified by region-of-interest-based lesion-symptom mapping (RLSM). Cortical structural alterations were examined by surface-based morphometry (SBM), in which the cortical thickness and fractal dimension were measured with three-dimensional magnetic resonance imaging (MRI). Fiber tracking on the human population-averaged diffusion MRI template was performed to examine whether the cortical structural alterations were associated with the syntax-related networks. The RLSM revealed associations between agrammatic comprehension and a glioma in the posterior limb of the left internal capsule. The SBM demonstrated that decreased cortical thickness and/or increased complexity of the right posterior insula were associated not only with agrammatic comprehension of the patients but also with the syntactic abilities of healthy participants. The fiber tracking revealed that the route between these two regions was anatomically integrated into the preexisting syntax-related networks previously identified. These results suggest a potential association between agrammatic comprehension in patients with diffuse glioma and structural variations in specific tracts and cortical regions, which may be closely related to the syntax-related networks.

Extracellular high molecular weight α-synuclein oligomers induce cell death by disrupting the plasma membrane

α-Synuclein (αS), the causative protein of Parkinson's disease and other α-synucleinopathies, aggregates from a low molecular weight form (LMW-αS) to a high molecular weight αS oligomer (HMW-αSo). Aggregated αS accumulates intracellularly, induces intrinsic apoptosis, is released extracellularly, and appears to propagate disease through prion-like spreading. Whether extracellular αS aggregates are cytotoxic, damage cell wall, or induce cell death is unclear. We investigated cytotoxicity and cell death caused by HMW-αSo or LMW-αS. Extracellular HMW-αSo was more cytotoxic than LMW-αS and was a crucial factor for inducing plasma membrane damage and cell death. HMW-αSo induced reactive oxygen species production and phospholipid peroxidation in the membrane, thereby impairing calcium homeostasis and disrupting plasma membrane integrity. HMW-αSo also induced extrinsic apoptosis and cell death by activating acidic sphingomyelinase. Thus, as extracellular HMW-αSo causes neuronal injury and death via cellular transmission and direct plasma membrane damage, we propose an additional disease progression pathway for α-synucleinopathies.

IgG index of cerebrospinal fluid can reflect pathophysiology associated with Lewy bodies in Parkinson's disease

BACKGROUND

Neuroinflammation is one of the pathophysiologies of Parkinson's disease (PD). Lewy bodies, the pathological hallmark of PD, emerge as a consequence of α-synuclein aggregation, and neuroinflammation is induced concurrently with this aggregation. Imaging and cerebrospinal fluid (CSF) biomarkers that reflect PD pathophysiology have been developed or are under investigation. The IgG index of CSF is a marker of inflammation, and may also reflect the pathophysiology of PD.

AIM

We examined if the IgG index reflects the pathophysiology of PD in drug-naïve PD patients.

METHOD

The subjects were 20 consecutive PD patients who underwent 123I-MIBG scintigraphy for assessment of the heart to mediastinum (H/M) ratio and wash out rate, 123I-Ioflupane SPECT for examination of the specific binding ratio in the striatum, and lumbar puncture before treatment. The CSF IgG index and levels of pathogenic proteins (total α-synuclein, oligomeric α-synuclein, total tau, phosphorylated tau and amyloid Aβ1-42) were determined. The IgG index was compared with the other parameters using Spearman correlation analysis.

RESULTS

The IgG index showed a significant correlation with the H/M ratio in early (r = -0.563, p = 0.010) and delayed (r = -0.466, p = 0.038) images in 123I-MIBG scintigraphy and with the CSF total tau level (r = -0.513, p = 0.021).

CONCLUSION

Neuroinflammation is involved in PD pathophysiology in some patients, and a higher IgG index indicates the presence of neuroinflammation accompanied by emergence of Lewy bodies.

Association Between Frequency of Social Contact and Brain Atrophy in Community-Dwelling Older People Without Dementia: The JPSC-AD Study

BACKGROUND AND OBJECTIVES

Epidemiologic evidence has shown that social isolation, a low frequency of social contact with others, is associated with the risk of dementia and late-life depressive symptoms. Therefore, we hypothesized that low frequency of social contact may be involved in brain atrophy, and depressive symptoms may play some role in this relationship. We aimed to evaluate the association between low frequency of social contact and the volumes of various brain regions and to assess the extent to which depressive symptoms mediate these relationships from a large population-based multisite cohort study.

METHODS

Dementia-free community-dwelling Japanese aged 65 years or older underwent brain MRI scans and a comprehensive health examination. Frequency of contact with noncohabiting relatives and friends was determined by asking a single question with 4 categories: everyday, several times a week, several times a month, and seldom. Total and regional brain volumes, intracranial volume (ICV), and white matter lesion volume were estimated using FreeSurfer software. The associations between frequency of social contact and brain volumes per ICV were examined using analyses of covariance. Mediation analyses were conducted to calculate the proportion of the associations explained by depressive symptoms.

RESULTS

We included 8,896 participants. The multivariable-adjusted mean of the total brain volume in the group with the lowest frequency of social contact was significantly lower compared with that in the group with the highest frequency of social contact (67.3% vs 67.8%), with a significant increasing trend across the groups (p value for trend <0.001). The white matter lesion volume increased significantly with lower frequency of social contact (0.30% in the lowest frequency group vs 0.26% in the highest frequency group, p value for trend <0.001). Lower frequency of social contact was associated with smaller volumes in the temporal lobe, occipital lobe, cingulum, hippocampus, and amygdala (all q values of false discovery rate correction <0.05). The relationships seemed to be partly mediated by depressive symptoms, which accounted for 15%-29% of the observed associations.

DISCUSSION

Lower frequency of social contact was associated with decreased total and cognitive function-related regional brain volumes. In addition, depressive symptoms partially explained the association in community-dwelling older people without dementia in Japan.

The Mechanisms of the Roles of α-Synuclein, Amyloid-β, and Tau Protein in the Lewy Body Diseases: Pathogenesis, Early Detection, and Therapeutics

Lewy body diseases (LBD) are pathologically defined as the accumulation of Lewy bodies composed of an aggregation of α-synuclein (αSyn). In LBD, not only the sole aggregation of αSyn but also the co-aggregation of amyloidogenic proteins, such as amyloid-β (Aβ) and tau, has been reported. In this review, the pathophysiology of co-aggregation of αSyn, Aβ, and tau protein and the advancement in imaging and fluid biomarkers that can detect αSyn and co-occurring Aβ and/or tau pathologies are discussed. Additionally, the αSyn-targeted disease-modifying therapies in clinical trials are summarized.

Metabolic changes in the plasma of mild Alzheimer's disease patients treated with Hachimijiogan

Background: Alzheimer's disease (AD), the most prevalent form of dementia, is a debilitating, progressive neurodegeneration. Amino acids play a wide variety of physiological and pathophysiological roles in the nervous system, and their levels and disorders related to their synthesis have been related to cognitive impairment, the core feature of AD. Our previous multicenter trial showed that hachimijiogan (HJG), a traditional Japanese herbal medicine (Kampo), has an adjuvant effect for Acetylcholine estelase inhibitors (AChEIs) and that it delays the deterioration of the cognitive dysfunction of female patients with mild AD. However, there are aspects of the molecular mechanism(s) by which HJG improves cognitive dysfunction that remain unclear. Objectives: To elucidate through metabolomic analysis the mechanism(s) of HJG for mild AD based on changes in plasma metabolites. Methods: Sixty-seven patients with mild AD were randomly assigned to either an HJG group taking HJG extract 7.5 g/day in addition to AChEI or to a control group treated only with AChEI (HJG:33, Control:34). Blood samples were collected before, 3 months, and 6 months after the first drug administration. Comprehensive metabolomic analyses of plasma samples were done by optimized LC-MS/MS and GC-MS/MS methods. The web-based software MetaboAnalyst 5.0 was used for partial least square-discriminant analysis (PLS-DA) to visualize and compare the dynamics of changes in the concentrations of the identified metabolites. Results: The VIP (Variable Importance in Projection) score of the PLS-DA analysis of female participants revealed a significantly higher increase in plasma metabolite levels after HJG administration for 6 months than was seen in the control group. In univariate analysis, the aspartic acid level of female participants showed a significantly higher increase from baseline after HJG administration for 6 months when compared with the control group. Conclusion: Aspartic acid was a major contributor to the difference between the female HJG and control group participants of this study. Several metabolites were shown to be related to the mechanism of HJG effectiveness for mild AD.

Exercise program to reduce the risk of cognitive decline and physical frailty in older adults: study protocol for an open label double-arm clinical trial

Objective

It is a big problem that many older adults are physically inactive. Well-known benefits of physical exercise include a decrease in the risk of cognitive decline and physical frailty. Therefore, this study aims to examine whether our proposed exercise program can prevent cognitive decline and improve physical function in the elderly.

Methods

This study will include nondemented older adults (n = 103) without regular exercise habits. The trial will include a physical exercise training program (once a week) and nutritional lectures (once a month) over 5 months and follow-up for ≥1 year. The primary endpoint is the program's efficacy in preventing cognitive decline, as assessed by changes in the memory performance index of the mild cognitive impairment (MCI) screen; the secondary endpoints are the incidence of MCI and dementia, physical testing, and frailty proportion. In the exploratory phase of the study, we will elucidate the underlying diseases causing MCI in community-dwelling older adults by neuroimaging.

Discussion

This double-arm trial that aims to assess the impact of physical exercise on nondemented older adults' cognitive and physical function. Furthermore, our newly developed exercise program will be easy for older adults to undertake.Clinical Trial Registration: https://clinicaltrials.gov/, identifier [jRCT 1040220140].

Plasma amyloid-β biomarkers are associated with Alzheimer's disease comorbidity in Lewy body disease

No blood biomarkers which can identify Alzheimer's disease pathology in Lewy body disease (LBD) have ever been established. We showed that the plasma amyloid-β (Aβ) _1-42/Aβ_1-40 ratio was significantly decreased in patients with Aβ+ LBD compared with those with Aβ- LBD and it might be a useful biomarker.

Structural Dynamics of Amyloid-β Protofibrils and Actions of Anti-Amyloid-β Antibodies as Observed by High-Speed Atomic Force Microscopy

Amyloid-β (Aβ) aggregation intermediates, including oligomers and protofibrils (PFs), have attracted attention as neurotoxic aggregates in Alzheimer's disease. However, due to the complexity of the aggregation pathway, the structural dynamics of aggregation intermediates and how drugs act on them have not been clarified. Here we used high-speed atomic force microscopy to observe the structural dynamics of Aβ42 PF at the single-molecule level and the effect of lecanemab, an anti-Aβ PF antibody with the positive results from Phase 3 Clarity AD. PF was found to be a curved nodal structure with stable binding angle between individual nodes. PF was also a dynamic structure that associates with other PF molecules and undergoes intramolecular cleavage. Lecanemab remained stable in binding to PFs and to globular oligomers, inhibiting the formation of large aggregates. These results provide direct evidence for a mechanism by which antibody drugs interfere with the Aβ aggregation process.

Detection of Atrial Fibrillation Using Insertable Cardiac Monitors in Patients With Cryptogenic Stroke in Japan (the LOOK Study): Protocol for a Prospective Multicenter Observational Study

BACKGROUND

Paroxysmal atrial fibrillation (AF) is a probable cause of cryptogenic stroke (CS), and its detection and treatment are important for the secondary prevention of stroke. Insertable cardiac monitors (ICMs) are clinically effective in screening for AF and are superior to conventional short-term cardiac monitoring. Japanese guidelines for determining clinical indications for ICMs in CS are stricter than those in Western countries. Differences between Japanese and Western guidelines may impact the detection rate and prediction of AF via ICMs in patients with CS. Available data on Japanese patients are limited to small retrospective studies. Furthermore, additional information about AF detection, including the number of episodes, cumulative episode duration, anticoagulation initiation (type and dose of regimen and time of initiation), rate of catheter ablation, role of atrial cardiomyopathy, and stroke recurrence (time of recurrence and cause of the recurrent event), was not provided in the vast majority of previously published studies.

OBJECTIVE

In this study, we aim to identify the proportion and timing of AF detection and risk stratification criteria in patients with CS in real-world settings in Japan.

METHODS

This is a multicenter, prospective, observational study that aims to use ICMs to evaluate the proportion, timing, and characteristics of AF detection in patients diagnosed with CS. We will investigate the first detection of AF within the initial 6, 12, and 24 months of follow-up after ICM implantation. Patient characteristics, laboratory data, atrial cardiomyopathy markers, serial magnetic resonance imaging findings at baseline, 6, 12, and 24 months after ICM implantation, electrocardiogram readings, transesophageal echocardiography findings, cognitive status, stroke recurrence, and functional outcomes will be compared between patients with AF and patients without AF. Furthermore, we will obtain additional information regarding the number of AF episodes, duration of cumulative AF episodes, and time of anticoagulation initiation.

RESULTS

Study recruitment began in February 2020, and thus far, 213 patients have provided written informed consent and are currently in the follow-up phase. The last recruited participant (May 2021) will have completed the 24-month follow-up in May 2023. The main results are expected to be submitted for publication in 2023.

CONCLUSIONS

The findings of this study will help identify AF markers and generate a risk scoring system with a novel and superior screening algorithm for occult AF detection while identifying candidates for ICM implantation and aiding the development of diagnostic criteria for CS in Japan.

TRIAL REGISTRATION

UMIN Clinical Trial Registry UMIN000039809; https://tinyurl.com/3jaewe6a.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/39307.

Relationships between squamous cell carcinoma antigen and cytokeratin 19 fragment values and renal function in oral cancer patients

Squamous cell carcinoma antigen (SCC-Ag) and cytokeratin 19 fragment (CYFRA) are used to screen and monitor oral cancer patients. However, recent studies have reported that tumour markers become elevated as renal function decreases, regardless of tumour progression. A retrospective study was performed of 423 oral cancer patients who underwent blood testing for these tumour markers and other blood analytes during a 10-year period. The values of SCC-Ag and CYFRA increased significantly with decreasing renal function (P < 0.01), and the values were abnormal at a median 2.6 ng/ml for SCC-Ag and 4.7 ng/ml for CYFRA in the group with estimated glomerular filtration rate (eGFR) values of< 30 ml/min/1.73 m². The factors that were related to the variation in tumour markers were albumin and creatinine. The cut-off values of eGFR were 59.7 ml/min/1.73 m² for SCC-Ag and 63.6 ml/min/1.73 m² for CYFRA, and the cut-off age when the tumour markers might rise due to the effect of renal function were 72 years for SCC-Ag and 73 years for CYFRA. In conclusion, decreased renal function should be taken into account when evaluating tumour markers in oral cancer. In addition, tumour markers are likely to be overestimated in patients over the age of 72-73 years.

Search for the Pair Production of Dark Particles X with K_{L}^{0}→XX, X→γγ

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110  MeV/c^{2} and 210-240  MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

Vacuoles related to tissue neuron-astrocyte ratio and infiltration of macrophages/monocytes contribute to hyperintense brain signals on diffusion-weighted magnetic resonance imaging in sporadic Creutzfeldt-Jakob disease

BACKGROUND

Radiological features in patients with sporadic Creutzfeldt-Jakob disease (sCJD) are hyperintensity of the cerebral cortex and the basal ganglia displayed by diffusion-weighted magnetic resonance imaging (DW-MRI). We performed a quantitative study on neuropathological and radiological findings.

METHODS

Patient 1 received a definite diagnosis of MM1-type sCJD, while patient 2 received a definite diagnosis of MM1 + 2-type sCJD. Two DW-MRI scans were performed on each patient. DW-MRI was either taken the day before or on the day of the patient's death, and several hyperintense or isointense areas were marked as a region of interest (ROI). Mean signal intensity of the ROI was measured. Pathological quantitative assessments of the vacuoles, astrocytosis, infiltration of monocytes/macrophages, and proliferation of microglia was performed. Vacuole load (% area vacuole), glial fibrillary acidic protein (GFAP), CD68, and Iba-1 load were calculated. We defined spongiform change index (SCI) to indicate vacuoles related to a tissue neuron-astrocyte ratio. We assessed the correlation of intensity of the last DW-MRI and the pathological findings as well as association of changes of the signal intensity on the sequential images and the pathological findings.

RESULT

We observed a strong positive correlation between SCI and DW-MRI intensity. In the analysis using serial DW-MRI and pathological findings, we found that CD68 load was significantly larger in areas where signal intensity decreased, as compared to those areas where hyperintensity remained unchanged.

CONCLUSION

DW-MRI intensity in sCJD is associated with the ratio of neuron to astrocyte in the vacuoles and the infiltration of macrophages and/or monocytes.

CKD, Brain Atrophy, and White Matter Lesion Volume: The Japan Prospective Studies Collaboration for Aging and Dementia

Rationale & Objective

Chronic kidney disease, defined by albuminuria and/or reduced estimated glomerular filtration rate (eGFR), has been reported to be associated with brain atrophy and/or higher white matter lesion volume (WMLV), but there are few large-scale population-based studies assessing this issue. This study aimed to examine the associations between the urinary albumin-creatinine ratio (UACR) and eGFR levels and brain atrophy and WMLV in a large-scale community-dwelling older population of Japanese.

Study Design

Population-based cross-sectional study.

Setting & Participants

A total of 8,630 dementia-free community-dwelling Japanese aged greater than or equal to 65 years underwent brain magnetic resonance imaging scanning and screening examination of health status in 2016-2018.

Exposures

UACR and eGFR levels.

Outcomes

The total brain volume (TBV)-to-intracranial volume (ICV) ratio (TBV/ICV), the regional brain volume-to-TBV ratio, and the WMLV-to-ICV ratio (WMLV/ICV).

Analytical Approach

The associations of UACR and eGFR levels with the TBV/ICV, the regional brain volume-to-TBV ratio, and the WMLV/ICV were assessed by using an analysis of covariance.

Results

Higher UACR levels were significantly associated with lower TBV/ICV and higher geometric mean values of the WMLV/ICV (P for trend = 0.009 and <0.001, respectively). Lower eGFR levels were significantly associated with lower TBV/ICV, but not clearly associated with WMLV/ICV. In addition, higher UACR levels, but not lower eGFR, were significantly associated with lower temporal cortex volume-to-TBV ratio and lower hippocampal volume-to-TBV ratio.

Limitations

Cross-sectional study, misclassification of UACR or eGFR levels, generalizability to other ethnicities and younger populations, and residual confounding factors.

Conclusions

The present study demonstrated that higher UACR was associated with brain atrophy, especially in the temporal cortex and hippocampus, and with increased WMLV. These findings suggest that chronic kidney disease is involved in the progression of morphologic brain changes associated with cognitive impairment.

Cerebrospinal Fluid Biomarkers and Amyloid-β Elimination from the Brain in Cerebral Amyloid Angiopathy-Related Inflammation

BACKGROUND

Cerebrospinal fluid (CSF) biomarkers in patients with cerebral amyloid angiopathy-related inflammation (CAA-ri) have demonstrated inconsistent results.

OBJECTIVE

We investigated the relationship between CSF amyloid-β protein (Aβ) and vascular pathological findings to elucidate the mechanisms of Aβ elimination from the brain in CAA-ri.

METHODS

We examined Aβ40 and Aβ42 levels in CSF samples in 15 patients with CAA-ri and 15 patients with Alzheimer's disease and cerebral amyloid angiopathy (AD-CAA) using ELISA as a cross-sectional study. Furthermore, we pathologically examined Aβ40 and Aβ42 depositions on the leptomeningeal blood vessels (arteries, arterioles, and veins) using brain biopsy samples from six patients with acute CAA-ri and brain tissues of two autopsied patients with CAA-ri.

RESULTS

The median Aβ40 and Aβ42 levels in the CSF showed no significant difference between pre-treatment CAA-ri (Aβ40, 6837 pg/ml; Aβ42, 324 pg/ml) and AD-CAA (Aβ40, 7669 pg/ml, p = 0.345; Aβ42, 355 pg/ml, p = 0.760). Aβ40 and Aβ42 levels in patients with post-treatment CAA-ri (Aβ40, 1770 pg/ml, p = 0.056; Aβ42, 167 pg/ml, p = 0.006) were lower than those in patients with pre-treatment CAA-ri. Regarding Aβ40 and Aβ42 positive arteries, acute CAA-ri cases showed a higher frequency of partially Aβ-deposited blood vessels than postmortem CAA-ri cases (Aβ40, 20.8% versus 3.9%, p = 0.0714; Aβ42, 27.4% versus 2.0%, p = 0.0714, respectively).

CONCLUSION

Lower levels of CSF Aβ40 and Aβ42 could be biomarkers for the cessation of inflammation in CAA-ri reflecting the recovery of the intramural periarterial drainage pathway and vascular function.

The Curcumin Derivative GT863 Protects Cell Membranes in Cytotoxicity by Aβ Oligomers

In Alzheimer's disease (AD), accumulation of amyloid β-protein (Aβ) is one of the major mechanisms causing neuronal cell damage. Disruption of cell membranes by Aβ has been hypothesized to be the important event associated with neurotoxicity in AD. Curcumin has been shown to reduce Aβ-induced toxicity; however, due to its low bioavailability, clinical trials showed no remarkable effect on cognitive function. As a result, GT863, a derivative of curcumin with higher bioavailability, was synthesized. The purpose of this study is to clarify the mechanism of the protective action of GT863 against the neurotoxicity of highly toxic Aβ oligomers (Aβo), which include high-molecular-weight (HMW) Aβo, mainly composed of protofibrils in human neuroblastoma SH-SY5Y cells, focusing on the cell membrane. The effect of GT863 (1 μM) on Aβo-induced membrane damage was assessed by phospholipid peroxidation of the membrane, membrane fluidity, membrane phase state, membrane potential, membrane resistance, and changes in intracellular Ca²⁺ ([Ca²⁺]i). GT863 inhibited the Aβo-induced increase in plasma-membrane phospholipid peroxidation, decreased membrane fluidity and resistance, and decreased excessive [Ca²⁺]i influx, showing cytoprotective effects. The effects of GT863 on cell membranes may contribute in part to its neuroprotective effects against Aβo-induced toxicity. GT863 may be developed as a prophylactic agent for AD by targeting inhibition of membrane disruption caused by Aβo exposure.

Effects of Melissa officinalis Extract Containing Rosmarinic Acid on Cognition in Older Adults Without Dementia: A Randomized Controlled Trial

BACKGROUND

Previous in vitro and in vivo studies on Alzheimer's disease (AD) models have reported that rosmarinic acid (RA) can inhibit the formation of amyloid-β fibrils as well as the oligomerization and deposition of amyloid-β protein. Melissa officinalis (M. officinalis) extract containing 500 mg of RA is tolerable and safe in healthy individuals and patients with mild AD dementia.

OBJECTIVE

This randomized placebo-controlled double-blind trial aimed to assess the effects of M. officinalis extract on cognition in older adults without dementia.

METHODS

This study included individuals who were diagnosed with subjective or mild cognitive impairment (n = 323). The trial involved M. officinalis extract supplementation (500 mg of RA per day) period of 96 weeks followed by a washout period of 24 weeks. The primary endpoint was the Alzheimer's Disease Assessment Scale-cognitive subscale score, and the secondary endpoints were other cognitive measure results as well as safety and tolerability.

RESULTS

There were no significant differences in cognitive measures between the placebo and M. officinalis groups from baseline to 96 weeks. However, based on the analysis of Clinical Dementia Rating Sum of Boxes scores in participants without hypertension, the score was found to be increased by 0.006 and decreased by 0.085 in the M. officinalis and placebo groups, respectively; this difference was statistically significant (p = 0.036). Furthermore, there were no differences in vital signs, physical and neurological measures, or hippocampal volume between the two groups.

CONCLUSION

These results indicate that M. officinalis extract may help prevent cognitive decline in older adults without hypertension.

CD59 Expression in Skeletal Muscles and Its Role in Myasthenia Gravis

Background and Objectives

Complement regulatory proteins at the neuromuscular junction (NMJ) could offer protection against complement-mediated damage in myasthenia gravis (MG). However, there is limited information on their expression at the human NMJ. Thus, this study aimed at investigating the expression of the cluster of differentiation 59 (CD59) at the NMJ of human muscle specimens and demonstrating the overexpression ofCD59mRNA and protein in the muscles of patients with MG.

Methods

In this observational study, muscle specimens from 16 patients with MG (9 and 7 patients with and without thymoma, respectively) and 6 nonmyopathy control patients were examined. Immunohistochemical stains, Western blot analysis, and quantitative real-time reverse transcription PCR were used to evaluate the CD59 expression.

Results

A strong localized expression of CD59 was observed at the NMJ in both patients with and without MG. Moreover, the CD59/glyceraldehyde-3-phosphate dehydrogenase protein ratio in patients with MG was significantly higher than that in the nonmyopathy controls (MG; n = 16, median 0.16, interquartile range (IQR) 0.08–0.26 and nonmyopathy controls; n = 6, median 0.03, IQR 0.02–0.11,p= 0.01). The proportion ofCD59mRNA expression relative toAChRmRNA expression (ΔCtCD59/AChR) was associated with the quantitative MG score, MG activities of daily living score, and MG of Foundation of America Clinical Classification (r= 0.663,p= 0.01;r= 0.638,p= 0.014; andr= 0.715,p= 0.003, respectively).

Discussion

CD59, which acts as a complement regulator, may protect the NMJ from complement attack. Our findings could provide a basis for further research that investigates the underlying pathogenesis in MG and the immunomodulating interactions of the muscle cells.

Cerebral white matter lesions and regional blood flow are associated with reduced cognitive function in early-stage cognitive impairment

Background

Differences in the extent of cerebral white matter lesions (WML) and regional cerebral blood flow (rCBF) in early-stage cognitive impairment (ESCI) contribute to the prognosis of cognitive decline; however, it is unclear precisely how WML and rCBF affect cognitive decline in ESCI.

Objective

We examined the association between WML, rCBF, and cognitive impairment in the ESCI, using path analysis to clarify how these variables affect each other.

Methods

Eighty-three patients who consulted our memory clinic regarding memory loss were included in this study based on the Clinical Dementia Rating. Participants underwent the Mini-Mental State Examination (MMSE), brain magnetic resonance imaging (MRI) for voxel-based morphometry analysis, and brain perfusion single-photon emission computed tomography (SPECT) for rCBF evaluation in cortical regions, using 3D stereotactic surface projection (3D-SSP) analysis.

Results

Path analysis was performed on the MRI voxel-based morphometry and SPECT 3D-SSP data, showing a significant correlation between both and MMSE scores. In the most suitable model (GFI = 0.957), correlations were observed between lateral ventricular (LV-V) and periventricular WML (PvWML-V) volumes [standardized coefficient (SC) = 0.326, p = 0.005], LV-V and rCBF of the anterior cingulate gyrus (ACG-rCBF; SC = 0.395, p < 0.0001), and ACG-rCBF and PvWML-V (SC = 0.231, p = 0.041). Furthermore, a direct relationship between PvWML-V and MMSE scores was identified (SC = -0.238, p = 0.026).

Conclusion

Significant interrelationships were observed among the LV-V, PvWML-V, and ACG-rCBF that directly affected the MMSE score in the ESCI. The mechanisms behind these interactions and the impact of PvWML-V on cognitive function require further investigation.

Predicting the Readmission and Mortality in Older Patients Hospitalized with Pneumonia with Preadmission Frailty

BACKGROUND

In older people, frailty has been recognized as an important prognostic factor. However, only a few studies have focused on multidimensional frailty as a predictor of mortality and readmission among inpatients with pneumonia.

OBJECTIVE

The present study aimed to assess the association between preadmission frailty and clinical outcomes after the hospitalization of older patients with pneumonia.

DESIGN

Single-center, retrospective case-control study.

SETTING

Acute phase hospital at Kobe, Japan.

PARTICIPANTS

The present study included 654 consecutive older inpatients with pneumonia.

MEASUREMENTS

Frailty status before admission was assessed using total Kihon Checklist (KCL) score, which has been used as a self-administered questionnaire to assess comprehensive frailty, including physical, social, and cognitive status. The primary outcome was a composited 6-month mortality and readmission after discharge.

RESULTS

In total, 330 patients were analyzed (median age: 79 years, male: 70.4%, median total KCL score: 10 points), of which 68 were readmitted and 10 died within 6 months. After multivariate analysis, total KCL score was associated with a composited 6-month mortality and readmission (adjusted hazard ratio, 1.07; 95% confidence interval, 1.02-1.12; p = 0.006). The cutoff value for total KCL score determined by receiver operating characteristic curve analysis was 15 points (area under the curve = 0.610). The group with a total KCL score ≥ 15 points had significantly higher readmission or mortality rates than the groups with a total KCL score < 15 points (p < 0.001).

CONCLUSIONS

Preadmission frailty status in older patients with pneumonia was an independent risk factor for readmission and survival after hospitalization.

Decreased circulating branched-chain amino acids are associated with development of Alzheimer's disease in elderly individuals with mild cognitive impairment

Background

Nutritional epidemiology has shown that inadequate dietary protein intake is associated with poor brain function in the elderly population. The plasma free amino acid (PFAA) profile reflects nutritional status and may have the potential to predict future changes in cognitive function. Here, we report the results of a 2-year interim analysis of a 3-year longitudinal study following mild cognitive impairment (MCI) participants.

Method

In a multicenter prospective cohort design, MCI participants were recruited, and fasting plasma samples were collected. Based on clinical assessment of cognitive function up to 2 years after blood collection, MCI participants were divided into two groups: remained with MCI or reverted to cognitively normal ("MCI-stable," N = 87) and converted to Alzheimer's disease (AD) ("AD-convert," N = 68). The baseline PFAA profile was compared between the two groups. Stratified analysis based on apolipoprotein E ε4 (APOE ε4) allele possession was also conducted.

Results

Plasma concentrations of all nine essential amino acids (EAAs) were lower in the AD-convert group. Among EAAs, three branched-chain amino acids (BCAAs), valine, leucine and isoleucine, and histidine (His) exhibited significant differences even in the logistic regression model adjusted for potential confounding factors such as age, sex, body mass index (BMI), and APOE ε4 possession (p < 0.05). In the stratified analysis, differences in plasma concentrations of these four EAAs were more pronounced in the APOE ε4-negative group.

Conclusion

The PFAA profile, especially decreases in BCAAs and His, is associated with development of AD in MCI participants, and the difference was larger in the APOE ε4-negative population, suggesting that the PFAA profile is an independent risk indicator for AD development. Measuring the PFAA profile may have importance in assessing the risk of AD conversion in the MCI population, possibly reflecting nutritional status.

Clinical trial registration

[https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000025322], identifier [UMIN000021965].

An exploratory, open-label, randomized, multicenter trial of hachimijiogan for mild Alzheimer’s disease

Background: Alzheimer’s disease (AD) is a progressive neurodegeneration and is the most prevalent form of dementia. Intervention at an early stage is imperative. Although three acetylcholinesterase inhibitors (AChEIs) are currently approved for the treatment of mild AD, they are not sufficiently effective. Novel treatments for mild AD are of utmost importance.

Objective: To assess the effectiveness of hachimijiogan (HJG), a traditional Japanese herbal medicine (Kampo), in the treatment of mild AD.

Methods: This exploratory, open-label, randomized, multicenter trial enrolled patients with mild AD whose score on the Mini Mental State Examination (MMSE) was over 21points. All participants had been taking the same dosage of AChEI for more than 3 months. The participants were randomly assigned to an HJG group taking HJG extract 7.5 g/day in addition to AChEI or to a control group treated only with AChEI. The primary outcome was the change from baseline to 6 months post treatment initiation on the Alzheimer’s Disease Assessment Scale-cognitive component- Japanese version(ADAS-Jcog). The secondary outcomes were change from baseline of the Instrumental Activity of Daily Life (IADL), Apathy scale, and Neuropsychiatric Inventory (NPI) -Q score.

Results: Among the 77 enrollees, the data of 69(34 HJG and 35 control)were available for analysis. The difference in the change of ADAS-Jcog from baseline to 6 months of the HJG and control groups was 1.29 (90% Confidence interval (CI), −0.74 to 3.32 p = 0.293). In the subgroup analysis, the differences in the change from baseline to 3 and 6 months for women were 3.70 (90% CI ,0.50 to 6.91, p = 0.059) and 2.90 (90% CI,0.09 to 5.71, p = 0.090), respectively. For patients over 65 years, the difference at 3 months was 2.35 (90%CI, 0.01 to 4.68 p = 0.099). No significant differences were found between the HJG and control groups in IADL score, Apathy scale, or NPI-Q score.

Conclusion: Although not conclusive, our data indicate that HJG has an adjuvant effect for acetylcholinesterase inhibitors and that it delays the deterioration of the cognitive dysfunction of mild Altzheimer’s disease patients.

Clinical Trial Registration:http://clinicaltrials.gov Japan Registry of clinical trials, identifier jRCTs 071190018

Amyloid-β: Structure, Function, and Pathophysiological Significance in Neurodegenerative Diseases

The rate of dementia continues to increase worldwide; however, there currently exist no therapeutic strategies for this condition [...]

Interactions of amyloid coaggregates with biomolecules and its relevance to neurodegeneration

The aggregation of amyloidogenic proteins is a pathological hallmark of various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In these diseases, oligomeric intermediates or toxic aggregates of amyloids cause neuronal damage and degeneration. Despite the substantial effort made over recent decades to implement therapeutic interventions, these neurodegenerative diseases are not yet understood at the molecular level. In many cases, multiple disease-causing amyloids overlap in a sole pathological feature or a sole disease-causing amyloid represents multiple pathological features. Various amyloid pathologies can coexist in the same brain with or without clinical presentation and may even occur in individuals without disease. From sparse data, speculation has arisen regarding the coaggregation of amyloids with disparate amyloid species and other biomolecules, which are the same characteristics that make diagnostics and drug development challenging. However, advances in research related to biomolecular condensates and structural analysis have been used to overcome some of these challenges. Considering the development of these resources and techniques, herein we review the cross-seeding of amyloidosis, for example, involving the amyloids amyloid β, tau, α-synuclein, and human islet amyloid polypeptide, and their cross-inhibition by transthyretin and BRICHOS. The interplay of nucleic acid-binding proteins, such as prions, TAR DNA-binding protein 43, fused in sarcoma/translated in liposarcoma, and fragile X mental retardation polyglycine, with nucleic acids in the pathology of neurodegeneration are also described, and we thereby highlight the potential clinical applications in central nervous system therapy.

Combined Treatment with Curcumin and Ferulic Acid Suppressed the Aβ-Induced Neurotoxicity More than Curcumin and Ferulic Acid Alone

Alzheimer’s disease (AD) is a neurodegenerative disease that leads to progressive cognitive decline. Several effective natural components have been identified for the treatment of AD. However, it is difficult to obtain conclusive evidence on the safety and effectiveness of natural components, because a variety of factors are associated with the progression of AD pathology. We hypothesized that a therapeutic effect could be achieved by combining multiple ingredients with different efficacies. The purpose of this study was thus to evaluate a combination treatment of curcumin (Cur) and ferulic acid (FA) for amyloid-β (Aβ)-induced neuronal cytotoxicity. The effect of Cur or FA on Aβ aggregation using thioflavin T assay was confirmed to be inhibited in a concentration-dependent manner by Cur single or Cur + FA combination treatment. The effects of Cur + FA on the cytotoxicity of human neuroblastoma (SH-SY5Y) cells induced by Aβ exposure were an increase in cell viability, a decrease in ROS and mitochondrial ROS, and repair of membrane damage. Combination treatment showed an overall higher protective effect than treatment with Cur or FA alone. These results suggest that the combined action mechanisms of Cur and FA may be effective in preventing and suppressing the progression of AD.

Deterioration after Liver Transplantation and Transthyretin Stabilizer Administration in a Patient with ATTRv Amyloidosis with a Leu58Arg (p.Leu78Arg) TTR Variant

We herein report a 44-year-old Japanese man with hereditary transthyretin amyloidosis (ATTRv amyloidosis) harboring the variant Leu58Arg (p.Leu78Arg) in TTR in whom we conducted an observational study with liver transplantation (LT) and transthyretin (TTR) stabilizers (tafamidis and diflunisal) for 9 years. This patient showed gradual deterioration of sensory, motor, and autonomic neuropathy symptoms after LT. Furthermore, cardiac amyloidosis gradually developed. Although the present case showed deterioration of the symptoms after disease-modifying treatments, LT might be suitable in patients with the same variant if they are young and in good condition due to a long survival after LT.

Association of the prefrailty with global brain atrophy and white matter lesions among cognitively unimpaired older adults: the Nakajima study

Physical frailty has been associated with adverse outcomes such as dementia. However, the underlying structural brain abnormalities of physical frailty are unclear. We investigated the relationship between physical frailty and structural brain abnormalities in 670 cognitively unimpaired individuals (mean age 70.1 years). Total brain volume (TBV), hippocampal volume (HV), total white matter hypointensities volume (WMHV), and estimated total intracranial volume (eTIV) on the 3D T1-weighted images were automatically computed using FreeSurfer software. Participants were divided into two states of physical frailty (robust vs. prefrail) based on the revised Japanese version of the Cardiovascular Health Study criteria. The multivariable-adjusted mean values of the TBV-to-eTIV ratio was significantly decreased, whereas that of the WMHV-to-eTIV ratio was significantly increased in the prefrail group compared with the robust group. Slowness, one of the components of physical frailty, was significantly associated with reduced TBV-to-eTIV and HV-to-eTIV ratios, and slowness and weakness were significantly associated with an increased WMHV-to-eTIV ratio. Our results suggest that the prefrail state is significantly associated with global brain atrophy and white matter hypointensities. Furthermore, slowness was significantly associated with hippocampal atrophy.

Diagnosis of Parkinson syndrome and Lewy-body disease using 123I-ioflupane images and a model with image features based on machine learning

OBJECTIVES

¹²³I-ioflupane has been clinically applied to dopamine transporter imaging and visual interpretation assisted by region-of-interest (ROI)-based parameters. We aimed to build a multivariable model incorporating machine learning (ML) that could accurately differentiate abnormal profiles on ¹²³I-ioflupane images and diagnose Parkinson syndrome or disease and dementia with Lewy bodies (PS/PD/DLB).

METHODS

We assessed ¹²³I-ioflupane images from 239 patients with suspected neurodegenerative diseases or dementia and classified them as having PS/PD/DLB or non-PS/PD/DLB. The image features of high or low uptake (F1), symmetry or asymmetry (F2), and comma- or dot-like patterns of caudate and putamen uptake (F3) were analyzed on 137 images from one hospital for training. Direct judgement of normal or abnormal profiles (F4) was also examined. Machine learning methods included logistic regression (LR), k-nearest neighbors (kNNs), and gradient boosted trees (GBTs) that were assessed using fourfold cross-validation. We generated the following multivariable models for the test database (n = 102 from another hospital): Model 1, ROI-based measurements of specific binding ratios and asymmetry indices; Model 2, ML-based judgement of abnormalities (F4); and Model 3, features F1, F2 and F3, plus patient age. Diagnostic accuracy was compared using areas under receiver-operating characteristics curves (AUC).

RESULTS

The AUC was high with all ML methods (0.92-0.96) for high or low uptake. The AUC was the highest for symmetry or asymmetry with the kNN method (AUC 0.75) and the comma-dot feature with the GBT method (AUC 0.94). Based on the test data set, the diagnostic accuracy for a diagnosis of PS/PD/DLB was 0.86 ± 0.04 (SE), 0.87 ± 0.04, and 0.93 ± 0.02 for Models 1, 2 and 3, respectively. The AUC was optimal for Model 3, and significantly differed between Models 3 and 1 (p = 0.027), and 3 and 2 (p = 0.029).

CONCLUSIONS

Image features such as high or low uptake, symmetry or asymmetry, and comma- or dot-like profiles can be determined using ML. The diagnostic accuracy of differentiating PS/PD/DLB was the highest for the multivariate model with three features and age compared with the conventional ROI-based method.

Transcranial Doppler for stratification of high-risk morphology of patent foramen ovale in patients with cryptogenic stroke

Microbubble testing using transcranial Doppler (TCD) is an important screening tool for diagnosing paradoxical cerebral embolism with high-risk PFO. However, little is known about the association between the microbubble test by TCD and the features of high-risk PFO evaluated by transesophageal echocardiography (TEE). We studied 101 consecutive patients at Showa University, from April 2019 to October 2020, who underwent both TCD and TEE with a sufficient Valsalva maneuver and who were strongly suspected by neurologists as cryptogenic stroke. According to the appearance of microbubbles as high-intensity transient signals (HITS), the TCD grade was stratified into three categories based on the criteria (A: none, no HITS, B: small; 1-10 HITS, and C: large; > 10 HITS, or an uncountable number of HITS). Among patients with RLS through the PFO in TEE, high-risk morphological features of PFO for cerebral embolism were evaluated as follows: (1) tunnel height, (2) tunnel length, (3) total excursion distance of the atrial septum into the right and left atrium, (4) existence of Eustachian valve or Chiari network, (5) angle of PFO from the inferior vena cava, and (6) large shunt (20 or more microbubbles). Of 101 patients (TCD grade; Group A = 49, Group B = 26, Group C = 26), RLS through PFO was detected in 37 patients (grade A = 8, grade B = 6, grade C = 23) by TEE. Among PFO-positive patients, tunnel height, length, total excursion distance into the right and left atria, angle of PFO from the inferior vena cava, and frequency of large shunt in TEE were significantly larger in grade C than in grade A and B (p < 0.05). Additionally, grade C patients had significantly more forms of high-risk PFOs than those in grades A and B when the six features of high-risk PFO were compared. A multivariate logistic regression demonstrated that the tunnel length of PFO and the presence of large shunt in TEE were independently associated with large HITS in TCD (odds ratio: 1.18 and 49.5, 95% confidence interval 1.043-1.337 and 10.05-244.3, p = 0.0086 and p < 0.0001, respectively). In conclusion, the existence of a large HITS detected by TCD may have a screening advantage in predicting the high-risk morphologies of PFO that can cause paradoxical cerebral embolism.

POS0970 SAME OR DIFFERENT? ANALYSIS OF SIMILARITIES AND DIFFERENCES OF CROHN’S DISEASE AND ULCERATIVE COLITIS IN SPONDYLOARTHRITIS: AN ANCILLARY ANALYSIS FROM THE WORLDWIDE ASAS-perSpA STUDY

Background

Crohn’s disease (CD) and ulcerative colitis (UC) are grouped as inflammatory bowel disease (IBD), and both are frequently found as extra-musculoskeletal manifestations in spondyloarthritis (SpA). Several studies have described the connection between SpA and IBD in both directions. Still until today, no studies have investigated possible differences in the musculoskeletal manifestations between the two main entities of inflammatory bowel disease: CD and UC.

Objectives

To evaluate the clinical characteristics associated with the presence of CD or UC in patients with spondyloarthritis from the international cross-sectional ASAS-perSpA study.

Methods

We analyzed 3152 patients from the ASAS per-SpA cohort who had a diagnosis of axial SpA or peripheral SpA according to the treating rheumatologist. Patients with IBD - confirmed by endoscopy - were identified and stratified by CD or UC. Patients in which their IBD disease was not specified, were excluded. Demographics, clinical characteristics, treatments and patient-reported outcomes were compared between both subgroups.

Results

Among the 146 patients diagnosed with IBD from the 3152 patients included in the analysis, 87 (59.6%) presented with CD (75 patients with axial SpA and 12 with peripheral SpA) and 39 (26.7%) with UC (34 patients with axial SpA and 5 with peripheral SpA) - Figure 1. A total of 20 (13.7%) patients with IBD were excluded, due to an inconclusive diagnosis of IBD. Patients with CD and UC had similar age (44.9 vs 44.0 years old) and sex distribution, although a slightly higher frequency of males was observed in CD than UC (63.2% vs 51.3%). The diagnostic delay for SpA was 7.0 years for CD and 8.1 years for UC. We did not find differences between both groups related to any musculoskeletal manifestations such as chronic back pain, uveitis, arthritis, enthesitis or dactylitis (Table 1). The only parameter showing a significant difference between CD and UC was the Bath Ankylosing Spondylitis Functional Index (BASFI) with a mean score of 3.3 vs 2.2 respectively (p=0.02) (Table 1). CD patients showed a higher tendency to be HLA-B27 positive (51.9% in CD vs. 39.4% in UC), but this did not reach statistical significance. No differences were observed regarding treatment patterns between both groups.

Table 1.

Demographics and clinical characteristics related to spondyloarthritis of patients with concomitant Crohn’s disease or ulcerative colitis (n=146).

Crohn’s Disease N=87Ulcerative Colitis N=39PAge, mean (SD)44.9 (13.5)44.0 (13.0)0.68Sex, n/N (%) male55/87 (63.2)20/39 (51.3)0.21Smoker ever, n/N (%)36/87 (41.4)19/39 (48.7)0.44Diagnostic delay of SpA (years), mean (SD)7.0 (6.9)8.8 (8.1)0.38Psoriasis ever, n/N (%)9/87 (10.3)6/39 (15.4)0.47Uveitis ever, n/N (%)17/87 (19.5)11/39 (28.2)0.28Synovitis ever, n/N (%)42/87 (48.3)18/39 (46.2)0.83Enthesitis ever, n/N (%)26/87 (29.9)14/39 (35.9)0.50Dactylitis ever, n/N (%)3/87 (3.4)1/39 (2.6)0.79Axial involvement ever (according to the rheumatologist), n/N (%)79/87 (90.8)37/39 (94.9)0.44Sacroiliitis on X-ray, n/N (%)64/87 (73.6)26/39 (66.7)0.19HLA-B27 positive, n/N (%)28/54 (51.9)13/33 (39.4)0.26CRP mg/L, mean (SD)11.1 (33.8)15.3 (30.1)0.13ASDAS-CRP, mean (SD)2.4 (1.0)2.4 (1.1)0.84BASFI, mean (SD) 0-103.3 (2.6)2.2 (2.1)0.02csDMARDs ever, n/N (%)71/87 (81.6)35/39 (89.7)0.25bDMARDs ever, n/N (%)72/87 (82.8)33/39 (84.6)0.80

ASDAS, Ankylosing Spondylitis Disease Activity Score; BASFI, Bath Ankylosing Spondylitis Functional Index; bDMARD, biological disease-modifying antirheumatic drugs; CRP, c-reactive protein; csDMARD, conventional synthetic disease-modifying antirheumatic drugs; SD, standard deviation; SpA, spondyloarthritis.

Conclusion

In our ancillary analysis of the ASAS-perSpA study in patients with SpA and concomitant CD or UC, no differences in the clinical presentation or demographic characteristics between the two subgroups were observed, except for the BASFI.

Disclosure of Interests

None declared

[Recommendations (Proposal) for promoting research for overcoming neurological diseases 2020]

The Japanese Society of Neurology discusses research, education, and medical care in the field of neurology and makes recommendations to the national government. Dr. Mizusawa, the former representative director of the Japanese Society of Neurology, selected committee members and made "Recommendations for Promotion of Research for Overcoming Neurological Diseases" in 2013. After that, the Future Vision Committee was established in 2014, and these recommendations have been revised once every few years by the committee. This time, the Future Vision Committee made the latest recommendations from 2020 to 2021. In this section I, we will discuss clinical and research topics of neurology categorized by the methodology, including genetic research, translational research, nucleic acid therapies, iPS research, and nursing/welfare.

[Recommendations (Proposal) for promoting research for overcoming neurological diseases 2020]

The Japanese Society of Neurology discusses research, education, and medical care in the field of neurology and makes recommendations to the national government. Dr. Mizusawa, the former representative director of the Japanese Society of Neurology, selected committee members and made "Recommendations for Promotion of Research for Overcoming Neurological Diseases" in 2013. After that, the Future Vision Committee was established in 2014, and these recommendations have been revised once every few years by the committee. This time, the Future Vision Committee made the latest recommendations from 2020 to 2021. In this section II, we will discuss clinical and research topics of neurology categorized by the diseases. In each field, the hot topic of the disease was described by the expert.

Prevalence of and risk factors for depressive symptoms in non-tuberculous mycobacterial pulmonary disease

BACKGROUND: The presence of depressive symptoms in patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) is an important research topic; however, the prevalence of depressive symptoms and the factors that influence their development are unclear.OBJECTIVE: To analyse the association between CES-D (Center for Epidemiological Studies Depression Scale) scores and clinical parameters such as age, disease duration, pulmonary function, imaging findings, blood data, physical functions, sleep disturbances, respiratory symptoms and health-related quality of life (HRQOL).METHODS: We conducted a cross-sectional retrospective study of 114 patients with NTM-PD at a single centre from March 2016 to January 2021 to evaluate the relationship between CES-D scores and clinical parameters.RESULTS: Participants had a median age of 64 years; 32.5% of them had depressive symptoms. Disease duration, albumin, C-reactive protein, pulmonary function, dyspnoea, exercise capacity, respiratory symptoms, cough-related HRQOL and sleep disturbances were associated with depressive symptoms. Binomial logistic regression analyses indicated that the CES-D score was significantly associated with cough-related HRQOL and sleep disturbances.CONCLUSION: A high percentage of NTM-PD patients in this study experienced depressive symptoms, and these patients had abnormalities of various clinical parameters. Cough-related HRQOL and sleep disturbance had a strong influence on the development of depressive symptoms.

Analysis of circulating microRNA during early gestation in Japanese black cattle

Circulating microRNAs (miRNAs) have been used as biomarkers for various diseases and physiological conditions in humans and mice; studies in domestic animals, particularly cattle, are limited. The importance of early pregnancy diagnosis (especially within the 21-d cow estrous cycle) in the livestock industry is extremely high. This study compared the circulating miRNAs in bred non-pregnant and pregnant Japanese Black cows, explored miRNAs as biomarkers for early pregnancy diagnosis, and established a measurement system that included selecting an appropriate reference miRNA and determining the effect of hemolysis on miRNA quantification in plasma. miRNA was extracted from the plasma of Japanese Black cows on day 21 after artificial insemination and subjected to a customized bovine oligonucleotide microarray for expression analysis. Differentially expressed miRNAs and reference miRNA candidates were selected and validated using reverse transcription-quantitative PCR (RT-qPCR). An appropriate endogenous reference miRNA for normalization was selected using NormFinder software. To evaluate the effect of hemolysis on miRNA quantification, hemolyzed samples were prepared using plasma from four cows in the estrous cycle and subjected to RT-qPCR. A total of 124 miRNAs were detected in bovine plasma by microarray analysis in bred non-pregnant and pregnant cows. The levels of five circulating miRNAs were significantly higher in pregnant cows than in bred non-pregnant cows, and 24 miRNAs were detected only in the pregnant group. NormFinder analysis and RT-qPCR validation showed that miR-2455 was an appropriate reference miRNA in the plasma of bred non-pregnant and pregnant Japanese Black cows, and miR-19b, miR-25, miR-29a, and miR-148a were significantly higher in the pregnant group. These four circulating miRNAs did not change during the estrous cycle and were less affected by hemolysis. In the current study, we found four miRNAs, miR-19b, miR-25, miR-29a, and miR-148a, which were present at high levels in the plasma of pregnant Japanese Black cows. Since these miRNAs are less affected by hemolysis, they may potentially be used as biomarkers for early pregnancy diagnosis in cattle.

Extracellular Vesicles Contribute to the Metabolism of Transthyretin Amyloid in Hereditary Transthyretin Amyloidosis

Hereditary (variant) transthyretin amyloidosis (ATTRv amyloidosis), which is caused by variants in the transthyretin (TTR) gene, leads to TTR amyloid deposits in multiple organs and various symptoms such as limb ataxia, muscle weakness, and cardiac failure. Interaction between amyloid proteins and extracellular vesicles (EVs), which are secreted by various cells, is known to promote the clearance of the proteins, but it is unclear whether EVs are involved in the formation and deposition of TTR amyloid in ATTRv amyloidosis. To clarify the relationship between ATTRv amyloidosis and EVs, serum-derived EVs were analyzed. In this study, we showed that cell-derived EVs are involved in the formation of TTR amyloid deposits on the membrane of small EVs, as well as the deposition of TTR amyloid in cells. Human serum-derived small EVs also altered the degree of aggregation and deposition of TTR. Furthermore, the amount of TTR aggregates in serum-derived small EVs in patients with ATTRv amyloidosis was lower than that in healthy controls. These results indicate that EVs contribute to the metabolism of TTR amyloid, and suggest that TTR in serum-derived small EVs is a potential target for future ATTRv amyloidosis diagnosis and therapy.

Transmission of Cerebral β-Amyloidosis Among Individuals

Deposition of amyloid β protein (Aβ) in the brain (cerebral β-amyloidosis) is a hallmark of Alzheimer's disease (AD). So far, there have been increasing number of experimental studies using AD mouse model that cerebral β-amyloidosis could be transmitted among individuals as prion-like mechanism. Furthermore, several pathological studies using autopsied patients with iatrogenic Creutzfeldt-Jakob disease (CJD) showed that cerebral β-amyloidosis in addition to the CJD pathology could be transmitted among humans via medical procedures, such as human growth hormone derived from cadaver injection and cadaveric dura mater graft. In addition, although cerebral amyloid angiopathy (CAA), which is Aβ deposition in the cerebral vessels, related cerebral hemorrhage rarely develops in young people, several patients with CAA-related cerebral hemorrhage under the age of 55 with histories of neurosurgeries with and without dura mater graft in early childhood have been reported. These patients might show that Aβ pathology is often recognized as Aβ-CAA rather than parenchymal Aβ deposition in the transmission of cerebral β-amyloidosis in humans, and we proposed an emerging concept, "acquired CAA". Considering that there have been several patients with acquired CAA with an incubation period from neurosurgery and the onset of CAA related cerebral hemorrhage of longer than 40 years, the number of cases is likely to increase in the future, and detailed epidemiological investigation is required. It is necessary to continue to elucidate the pathomechanisms of acquired CAA and urgently establish a method for preventing the transmission of cerebral β-amyloidosis among individuals.

Single-molecule Observation of Self-Propagating Amyloid Fibrils

The assembly of misfolded proteins into amyloid fibrils is associated with amyloidosis, including neurodegenerative diseases, such as Alzheimer’s, Parkinson’s, and prion diseases. The self-propagation of amyloid fibrils is widely observed in the aggregation pathways of numerous amyloidogenic proteins. This propensity with plasticity in primary nucleation allows amyloid fibril polymorphism, which is correlated with the pathology/phenotypes of patients. Because the interference with the nucleation and replication processes of amyloid fibrils can alter the amyloid structure and the outcome of the disease, these processes can be a target for developing clinical drugs. Single-molecule observation of amyloid fibril replication can be an experimental system to provide the kinetic parameters for simulation studies and confirm the effect of clinical drugs. Here, we review single-molecule observation of the amyloid fibril replication process using fluorescence microscopy and time-lapse atomic force microscopy, including high-speed atomic force microscopy. We discussed the amyloid fibril replication process and combined single-molecule observation results with molecular dynamics simulations.

Mini Abstract Structural dynamics in amyloid aggregation is related with various Alzheimer’s and Parkinson’s disease symptoms. Single-molecule observation using high-speed atomic force microscopy can directly visualize the structural dynamics of individual amyloid aggregate assemblies. Here, we review historical and recent studies of single-molecule observation of amyloid aggregation with supportive molecular dynamics simulation.

Voxel-based analysis of age and gender effects on striatal [123I] FP-CIT binding in healthy Japanese adults

OBJECTIVE

Although previous studies have investigated age and gender effects on striatal subregional dopamine transporter (DaT) binding, these studies were mostly based on a conventional regions of interest-based analysis. Here, we investigated age and gender effects on striatal DaT binding at the voxel level, using a multicenter database of [(¹²³)I] N-omega-fluoropropyl-2beta-carbomethoxy-3beta-{4-iodophenyl}nortropane ([(¹²³)I] FP-CIT)-single photon emission computed tomography (SPECT) scans in 256 healthy Japanese adults.

METHODS

We used the Southampton method to calculate the specific binding ratios (SBRs) of each subject's striatum and then converted the [¹²³I] FP-CIT SPECT images to quantitative SBRs images. To investigate the effects of age and gender effects on striatal DaT binding, we performed a voxel-based analysis using statistical parametric mapping. Gender differences were also compared between young to middle-aged subjects and elderly subjects (age threshold: 60 years).

RESULTS

When all subjects were explored as a group, DaT binding throughout the striatum decreased with advancing age. Among all subjects, the females showed higher DaT binding in the bilateral caudate compared to the males. In the young to middle-aged subjects, the females showed higher DaT binding throughout the striatum (with a slight caudate predominance) versus the males. In the elderly, there were no gender differences in striatal DaT binding.

CONCLUSION

Our findings of striatal subregional age- and gender-related differences may provide useful information to construct a more detailed DaT database in healthy Japanese subjects.