Background: The Hong Kong Brief Cognitive Test (HKBC), a brief instrument designed to screen for cognitive impairment in older adults, has been validated in Cantonese-speaking populations and has shown better performance than the Mini-Mental State Examination (MMSE) in detecting both mild and major neurocognitive disorder (NCD). Objective: This study aimed to validate the HKBC for detecting patients with amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease (AD) in a Mandarin-speaking Chinese population. Methods: Two hundred forty-eight patients with aMCI, 67 patients with mild AD and 306 healthy controls (HCs) were recruited for this study and completed both the HKBC and the MMSE. The performance of the HKBC and MMSE in distinguishing patients with aMCI from HCs and distinguishing patients with AD from patients with aMCI was compared in the whole population and in age- and education-stratified subgroups. Results: The optimal HKBC cutoff score for distinguishing patients with aMCI from HCs was 23, and the optimal cutoff score for distinguishing patients with AD from patients with aMCI was 17. The HKBC significantly outperformed the MMSE at differentiating patients with aMCI from HCs in the whole population ( z = 12.38, p < 0.01) and all subgroups stratified by age or education. Regarding the discrimination of patients with AD from patients with aMCI, the HKBC showed better performance than the MMSE in the oldest subgroup ( z = 2.18, p = 0.03). Conclusion: The HKBC is a sensitive and specific screening tool for detecting aMCI and AD in the Chinese population across age groups and educational levels.

A growing body of evidence indicates that atherosclerosis is correlated with cerebral small vessel disease and contributes to cognitive decline. This study aimed to explore the characteristics and contributions of intracranial hemodynamics and carotid atherosclerosis to cognitive dysfunction in subjects with subcortical ischemic vascular dementia (SIVD). Notably, 44 patients with SIVD, 30 patients with Alzheimer's disease (AD), and 30 healthy controls (HCs) were recruited from our longitudinal MRI study for AD and SIVD (ChiCTR1900027943). The cerebral mean flow velocity (MFV) and pulsatility index (PI) of both anterior and posterior circulations, artery plaque, and lumen diameter in carotid arteries were investigated using transcranial Doppler and carotid ultrasound, respectively. Their correlations with cognitive function were analyzed in patients with dementia. Decreased MFV and increased PI were found in patients with SIVD and AD. Patients with SIVD showed lower MFV and higher PI in the bilateral posterior cerebral arteries compared to patients with AD. Increases in lumen diameter, number of arteries with plaque, and total carotid plaque score were found in patients with SIVD. The Mini-Mental State Examination score was positively correlated with the MFV and negatively correlated with the PI of most major cerebral arteries, while it was negatively correlated with the lumen diameter of the common carotid artery, number of arteries with plaque, and total carotid plaque score in patients with dementia. There were also correlations between these parameters of some arteries and memory and executive function. Our results provide additional evidence suggesting that the pathological changes in macrovascular structure and function are correlated with cognitive impairment in dementia patients with SIVD and to a lesser extent AD.

原发性进行性失语(primary progressive aphasia,PPA)是一组以语言障碍为早期显著特征的综合征,包括非流利型(nonfluent/agrammatic variant PPA, nfvPPA)、语义型(semantic variant PPA,svPPA)和语素减少型(logopenic variant PPA,lvPPA)3种主要类型[1].nfvPPA表现为语言表达费力(言语失用)或语法缺失,可能存在对较复杂句子的理解障碍;svPPA表现为对单个词理解障碍和命名障碍,可伴有客观知识损伤,以及表层失读或失写;lvPPA表现为自发言语和命名中的单个词语提取受损(找词困难),以及句子和短语的复述障碍,自发言语中可存在语音错误[2].PPA早期的语言障碍不易被准确识别,除了病史以及语言和其他认知功能评估,诊断更多依赖于头颅MRI、单光子发射计算机断层成像(SPECT)和正电子发射断层成像(PET)等影像学支持.本综述采用以上影像学技术进行系统回顾和分析,比较不同亚型PPA的结构、功能和分子影像学特点及其诊断价值,以阐述PPA的脑功能改变和分子病理机制.

OBJECTIVE:Deficits in the semantic learning strategy were observed in subjects with amnestic mild cognitive impairment (aMCI) in our previous study. In the present study, we explored the contributions of executive function and brain structure changes to the decline in the semantic learning strategy in aMCI. METHODS:A neuropsychological battery was used to test memory and executive function in 96 aMCI subjects and 90 age- and gender-matched healthy controls (HCs). The semantic clustering ratio on the verbal learning test was calculated to evaluate learning strategy. Medial temporal lobe atrophy (MTA) and white matter hyperintensities (WMH) were measured on MRI with the MTA and Fazekas visual rating scales, respectively. RESULTS:Compared to HCs, aMCI subjects had poorer performance in terms of memory, executive function, and the semantic clustering ratio (P < .001). In aMCI subjects, no significant correlation between learning strategy and executive function was observed. aMCI subjects with obvious MTA demonstrated a lower semantic clustering ratio than those without MTA (P < .001). There was no significant difference in the learning strategies between subjects with high-grade WMH and subjects with low-grade WMH. CONCLUSION:aMCI subjects showed obvious impairment in the semantic learning strategy, which was attributable to MTA but independent of executive dysfunction and subcortical WMH. These findings need to be further validated in large cohorts with biomarkers identified using volumetric brain measurements. (JINS, 2019, 25, 706-717).

Cerebral hypoperfusion is an important factor in the pathogenesis of cerebrovascular diseases and neurodegenerative disorders. We investigated the effects of memantine and rosuvastatin on both neovascularization and synaptic function in a rat model of chronic cerebral hypoperfusion, which was established by the bilateral common carotid occlusion (2VO) method. We tested learning and memory ability, synaptic function, circulating endothelial progenitor cell (EPC) number, expression of neurotrophic factors, and markers of neovasculogenesis and cell proliferation after memantine and/or rosuvastatin treatment. Rats treated with memantine and/or rosuvastatin showed significant improvement in Morris water maze task and long-term potentiation (LTP) in the hippocampus, compared with untreated 2VO model rats. Circulating EPCs, expression of brain-derived neurotrophic factor, and vascular endothelial growth factor, markers of microvessel density were increased by each of the three interventions. Rosuvastatin also increased cell proliferation in the hippocampus. Combined treatment with memantine and rosuvastatin showed greater effect on enhancement of LTP and expression of neurotrophic factors than either single medication treatment alone. Both memantine and rosuvastatin improved learning and memory, enhanced neovascularization and synaptic function, and upregulated neurotrophic factors in a rat model of chronic cerebral hypoperfusion.

Background: Expression of neuronal thread protein (NTP), which is considered to be related to neuritic sprouting and neuronal death, may be elevated in brain tissue, cerebrospinal fluid, and even urine in patients with Alzheimer's disease (AD). Objective: In this study, we analyzed the correlation between urine AD-associated NTP (AD7c-NTP) level, and amyloid-beta (A beta) deposition, and clinical symptoms in AD and mild cognitive impairment (MCI). Methods: Twenty-two patients with mild to moderate AD and 8 subjects with MCI were recruited. A beta deposition was measured with [C-11]-labeled Pittsburgh compound B (PiB)-positron emission tomography (PET) in all participants. Urine AD7c-NTP levels were measured using enzyme-linked immunosorbent assay. Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI) were used to evaluate cognitive function and behavioral psychological symptoms, respectively. Results: Fourteen (63.6%) ofADpatients and 2 (25.0%) of MCI subjects were A beta positive on PiB-PET. There was a significant difference in urine AD7c-NTP level between A beta positive ( 2.27 +/- 2.22 ng/ml) and negative (0.55 +/- 0.60 ng/ ml) subjects (p = 0.018). Using 1.46 ng/ml as a cut-off value, 68.8% of A beta positive subjects showed elevated urine AD7c-NTP level, and 92.9% of A beta negative subjects showed normal urine AD7c-NTP level. There were no relationships between urine AD7c-NTP level and MMSE and total NPI scores. However, AD7c-NTP level positively correlated with agitation score on NPI. Conclusions: Urine AD7c-NTP had high specificity and moderate sensitivity in predicting A beta deposition among patients with cognitive impairment. Furthermore, urine AD7c-NTP level strongly correlated with the symptom of agitation.

ABSTRACT Background: Cognition and sleep deficits occur in amnestic mild cognitive impairment (aMCI) and vascular cognitive impairment-no dementia (VCIND). However, how memory and sleep deficits differ between aMCI and VCIND remains unclear. Methods: Fifty aMCI and 50 VCIND patients and 38 sex- and age-matched healthy controls (HCs) were administered the Hopkins Verbal Learning Test-Revised (HVLT-R), Trail Making Test-A/B (TMT-A/B), Wisconsin Card Sorting Test (WCST), Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), Benton Judgment of Line Orientation (JLO) test, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Insomnia Severity Index (ISI) to quantify cognitive deficits and subjective sleep disturbance. Results: Compared with VCIND patients, aMCI patients had lower HVLT-R scores for total recall ( p < 0.001), delayed recall ( p < 0.001) and recognition ( p = 0.001), and for total-recall ( p = 0.002) and delayed-recall ( p < 0.001) semantic clustering ratios (SCRs). However, VCIND patients exhibited more obvious executive dysfunction (TMT-A, p < 0.001; TMT-B, p < 0.001; WCST, p < 0.001), lower information processing speed (PASAT, p = 0.003; SDMT, p < 0.001), and more severe sleep disturbance (PSQI, p < 0.001; ESS, p < 0.001; ISI, p < 0.001). Additionally, sleep quality and efficiency were related to total and delayed recall (all r values from −0.31 to −0.60, p < 0.05) in aMCI and VCIND. Conclusions: aMCI and VCIND differ in cognitive function, memory strategy and sleep impairment; these characteristics are helpful to identify and distinguish patients with very early cognitive impairment. Our results also suggest that memory deficits are associated with sleep disturbance in aMCI and VCIND.

Hydroxysafflor yellow A (HSYA) is a drug that exerts angiogenesis regulatory and neuroprotective effects and has become an effective therapy for brain and heart ischemic disorders. There is no definite evidence supporting a therapeutic effect of HSYA in vascular dementia (VaD). We used HSYA in a rat model of chronic cerebral ischemia to determine its potential therapeutic effects in VaD. The Morris water maze (MWM) was used to evaluate spatial cognitive function, and long-term potentiation (LTP) was tested as a marker of synaptic plasticity. The expression levels of brain-derived neurotrophic factor (BDNF) and two subunits of N-methyl-d-aspartate receptor (NMDAR; GluN2A and GluN2B) in the hippocampus were measured via western blotting. The MWM results showed that the experimental VaD group had longer escape latencies than the sham group, whereas the HSYA group had a decreased escape latency compared with the VaD group (P<0.05). The LTP at CA3-CA1 synapses in the hippocampus was also enhanced in the HSYA compared with the VaD group (P<0.05). The western blotting results revealed lower hippocampal BDNF and GluN2B expression in the VaD group compared with the sham group and significantly higher hippocampal expression in the HSYA group compared with the VaD group. No significant change in GluN2A expression was detected. The results indicate that HSYA may enhance the endogenous expression of BDNF and GluN2B, which are associated with the synaptic plasticity of the hippocampus, and may improve spatial learning and memory abilities in a rat model of VaD.

Objective To study the effect of repetitive transcranial magnetic stimulation(rTMS)on learning and memory of vascular dementia(VaD)rats.Methods Twenty male SD rats were divided into sham operation group(n=6),VaD group(n=6),and rTMS group(n=8).Their spatial learning and memory were assessed by Morris water maze test after rTMS.Their LTP was recorded.Expression of BDNF and NMDAR in hippocampus was detected by Western blot and immunohistochemistry respectively.Morphology of cells in CA1 and CA3 was observed with HE staining.Results Morris water maze test showed that the average escape lantent period was significantly longer in VaD group and rTMS group than in sham operation group and significantly shorter in rTMS group than in VaD group(P0.05).The swimming time and the swimming distance proportion of the total distance in platform quadrant were significantly shorter in VaD group and rTMS group than in sham operation group(P0.05).The LTP and expression levels of BDNF and NMDAR1 were significantly higher in rTMS group than in VaD group(P0.05).Optical microscopy showed that the arrangement and damage of nerve cells in CA1 and CA3were noticeably improved in rTMS group.Conclusion rTMS promotes LTP and improves spatial memory and congnition in VaD rats by upregulating the expression of BDNF and NMDAR in hippocampus.

Hydroxysafflor yellow A (HSYA) has angiogenesisregulating and neuro-protective effects, but its effects on vascular dementia (VaD) are unknown. In this study, 30 adult Sprague-Dawley rats were randomly allocated to five groups: normal, sham-operation, VaD alone (bilateral carotid artery occlusion), VaD plus saline (control), and VaD plus HSYA. One week after operation, the HSYA group received one daily tail-vein injection of 0.6 mg/100 g HSYA for two weeks. Five weeks after operation, the spatial memory of all five groups was evaluated by the water maze task, and synaptic plasticity in the hippocampus was assessed by the long-term potentiation (LTP) method. Vascular endothelial growth factor (VEGF) and N-methyl-Daspartic acid receptor 1 (NR1) expression in the hippocampus was detected via Western blot. We found that, compared with the group with VaD alone, the group with HSYA had a reduced escape latency in the water maze (P < 0.05), and the LTP at CA3-CA1 synapses in the hippocampus was enhanced (P < 0.05). Western blot in the late-phase VaD group showed slight up-regulation of VEGF and downregulation of NR1 in the hippocampus, while HSYA significantly up-regulated both VEGF and NR1. These results suggested that HSYA promotes angiogenesis and increases synaptic plasticity, thus improving spatial learning and memory in the rat model of VaD.