Publications by authors named "Asuka Koyama"

Background: An increase in choroid plexus (CP) volume may be associated with cognitive decline in older individuals without dementia. In this study, we aimed to clarify whether CP volume can serve as an imaging marker of cognitive decline, determine how strongly CP volume is associated with cognitive decline, and explore factors associated with CP volume in older adults.

Methods: We measured CP volume, brain parenchyma, and cerebrospinal fluid (CSF) spaces associated with disproportionately enlarged subarachnoid space hydrocephalus (DESH), an imaging feature of normal-pressure hydrocephalus, in community-dwelling older adults aged ≥ 65 years without dementia.

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  • The IPBES invasive alien species assessment is the first comprehensive global review focusing on the threats posed by invasive species to biodiversity and human wellbeing, synthesizing over 13,000 scientific and local knowledge sources.
  • It reveals significant and escalating threats from invasive alien species and outlines practical management strategies for addressing these challenges.
  • The assessment has garnered support from 143 member states, urging immediate action against biological invasions to protect ecosystems and communities worldwide.
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Previous studies of motility at low temperatures in have been conducted at temperatures of up to 15 °C. In this study, we report that exhibits unique motility at a lower temperature range (-8.7 to 1.

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Background: Gesture imitation, a simple tool for assessing visuospatial/visuoconstructive functions, is reportedly useful for screening and diagnosing dementia. However, gesture imitation performance in healthy older adults is largely unknown, as are the factors associated with lower performance. To address these unknowns, we examined the gesture imitation performance of a large number of community-dwelling older adults aged ≥65 years in Arao City, Kumamoto Prefecture (southern Japan).

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Insect galls, which often have complex external and internal structures, are believed to have adaptive significance for the survival of insects inside galls. A unique internal structure was discovered in the gall of a new cynipid species, Belizinella volutum Ide & Koyama, sp. nov.

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The invasion of alien plants has been rapidly proceeding worldwide due to urbanisation. This might be beneficial to wild pollinating insects, since some alien plant species have large flowers and/or long flowering periods, which can increase nectar sugar and pollen availability. To determine the relative contribution of alien plants to floral resource supply and whether resource-rich alien plants, if any, serve as an important food source of pollinating insects, we performed year-round field observations in suburban riverbanks.

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Background: Caring for patients with dementia with Lewy bodies (DLB) would be more stressful for their caregivers than those with Alzheimer's disease (AD). In this study, we compared levels of caregiver burden and the possible influential factors on the caregiver burden between DLB and AD.

Methods: Ninety-three DLB patients and 500 AD patients were selected from the Kumamoto University Dementia Registry.

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We surveyed woody plants, including oaks and chestnuts (Quercus L. and Castanea Mill.), and recorded the inhabiting galls induced by oak gall wasps (Hymenoptera: Cynipidae: Cynipini) at seven Japanese semi-natural grassland sites maintained by traditional regular burning with two of the seven abandoned grassland areas.

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  • Impaired cerebrospinal fluid (CSF) dynamics are linked to neurodegenerative diseases and brain health in older adults, with the study focusing on disproportionally enlarged subarachnoid-space hydrocephalus (DESH) related to aging.
  • The researchers used magnetic resonance imaging to analyze CSF regions in individuals aged 65 and older, finding significant volume changes associated with age, particularly in ventricular and Sylvian fissure spaces, while subarachnoid space volumes remained unchanged.
  • Results indicated that higher ventricular and Sylvian fissure volumes correlate with lower overall brain volume, and lower cognitive performance (Mini-Mental State Examination scores) was associated with certain CSF volume changes, highlighting the complexity of age-related
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Cognitive frailty (CF) is a clinical condition defined by the presence of both mild cognitive impairment (MCI) and physical frailty (PF). Elderly with CF are at greater risk of dementia than those with MCI or PF alone, but there are few known clinical or neuroimaging features to reliably distinguish CF from PF or MCI. We therefore conducted a population-based cross-sectional study of community elderly combining physical, cognitive, neuropsychiatric, and multisequence magnetic resonance imaging (MRI) evaluations.

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Background: Postoperative delirium is associated with increased mortality. Therefore, it is important to manage delirium during the entire perioperative period. Preoperative anxiety is associated with poor prognosis in postoperative patients who have undergone cardiovascular surgery.

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Unintentional seed introduction mediated by visitor's clothing and footwear is a major source of biological invasion into natural areas. To effectively avert these unintentional introductions, we must understand the links that connect relevant knowledge and desired outcome (i.e.

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Objective: To investigate the behavioral characteristics of semantic dementia (SD) using an instrument originally developed for patients with autism spectrum disorder.

Methods: The behavioral symptoms of 20 patients with SD and 20 patients with Alzheimer's disease (AD) in both the preclinical state and the dementia state were evaluated using the Pervasive Developmental Disorders Autism Society Japan Rating Scale (PARS).

Results: The SD group showed high prevalence in four behaviors related to stereotypy and social impairment: eating very few food items, selfishness, difficulty in recognizing others' feeling and thoughts, and interpreting language literally.

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  • * A sample of 718 AD patients underwent logistic regression analysis, revealing strong correlations between certain MMSE subitems and both the Physical Self-maintenance Scale (PSMS) and Lawton's Instrumental ADL (L-IADL).
  • * Findings suggest that instead of just focusing on the overall MMSE score, understanding the individual subitem performance can provide valuable insights for better ADL care and early interventions.
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Background/aims: Age-related changes in impairments in activities of daily living (ADL) in older adults with very mild Alzheimer's disease (vmAD) have been scarcely explored. We clarified the characteristics of ADL impairment and examined how ADL impairments differed by age in such patients compared with community-dwelling cognitively normal older adults.

Methods: The participants were 107 older adults with vmAD (Mini-Mental State Examination [MMSE] score ≥24), all of whom were first-visit outpatients at the Dementia Clinic of the Department of Neuropsychiatry, Kumamoto University Hospital.

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Objectives: Patients with Alzheimer's disease (AD) experience a gradual loss in their ability to perform instrumental activities of daily living (IADLs) from the early stage. A better understanding of the possible factors associated with IADL decline is important for the development of effective rehabilitation and support programs for patients with AD. Thus, we examined the relationships between comprehensive cognitive functions and neuropsychiatric symptoms and IADLs in patients with very mild AD.

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Background: Although cerebral microbleeds (CMBs) are commonly observed in patients with Alzheimer's disease (AD), their clinical relevance for AD remains unclear.

Objective: We investigated the significance of CMBs in AD by examining the relationship between CMBs and cerebral blood flow (CBF) in patients with AD.

Methods: Thirty-four patients (aged 77.

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Introduction: To keep up appearances, people with dementia sometimes pretend to know the correct answer, as seen during administration of neuropsychological tests such as the Mini-Mental State Examination (MMSE). These saving appearance responses (SARs) of people with dementia often lead to caregivers and/or medical staff underestimating the severity of dementia and impede proper early initiation of treatment. However, most descriptions of SARs are based on empirical knowledge of clinicians.

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Land-use changes cause biodiversity loss in semi-natural ecosystems worldwide. Biotic homogenization has led to biodiversity loss, mainly through declines in species composition turnover. Elucidating patterns of turnover in species composition could enhance our understanding of how anthropogenic activities affect community assembly.

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Background: Caregiver burden is a serious concern for family caregivers of dementia patients, but its nature is unclear in patients with semantic dementia (SD). This study aimed to clarify caregiver burden for right- (R > L) and left-sided (L > R) predominant SD versus behavioral-variant frontotemporal dementia (bvFTD) patients.

Methods: Using the Japanese version of the Zarit Burden Interview (ZBI) and the Neuropsychiatric Inventory, we examined caregiver burden and behavioral and psychological symptoms of dementia (BPSD) in 43 first-visit outpatient/family caregiver dyads (bvFTD, 20 dyads; SD [L > R], 13 dyads; SD [R > L], 10 dyads).

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Background: Toritsukuroi is a particular type of behaviour intended to save face or preserve appearances. Clinicians often observe toritsukuroi in people with dementia, but current knowledge about this behaviour is based on clinicians' empirical knowledge rather than on observational studies. This study was designed to clarify which behaviours are related to toritsukuroi based on neuropsychological examinations.

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Malnutrition among dementia patients is an important issue. However, the biochemical markers of malnutrition have not been well studied in this population. The purpose of this study was to compare biochemical blood markers among patients with Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and frontotemporal lobar degeneration (FTLD).

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