The electroencephalogram (EEG) signal is a general reflection of the neurophysiological activity of the brain, which has the advantages of being safe, efficient, real-time and dynamic. With the development and advancement of machine learning research, automatic diagnosis of Alzheimer’s diseases based on deep learning is becoming a research hotspot. Started from feedforward neural networks, this paper compared and analysed the structural properties of neural network models such as recurrent neural networks, convolutional neural networks and deep belief networks and their performance in the diagnosis of Alzheimer’s disease. It also discussed the possible challenges and research trends of this research in the future, expecting to provide a valuable reference for the clinical application of neural networks in the EEG diagnosis of Alzheimer’s disease.
Objective To systematically review the effect of vitamin D (VitD) supplementation on cognitive function in people with cognitive impairment and non-cognitive disorders. MethodsThe PubMed, Web of Science, Cochrane Library, EMbase, CBM, CNKI, WanFang Data and VIP databases were searched to collect randomized controlled trials (RCTs) about the effect of VitD supplementation on cognitive function of patients with cognitive impairment or non-cognitive disorders from inception to March, 2022. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed using RevMan 5.4 software. Results A total of 19 articles including 8 684 cases were included. The results of meta-analysis showed that mini-mental state examination (MMSE) score (MD=1.70, 95%CI 1.20 to 2.21, P<0.01), Montreal cognitive assessment (MoCA) score (MD=1.51, 95%CI 1.00 to 2.02, P<0.01), Wechsler Adult Intelligence Scale-Revised (WAIS-RC) score (MD=9.12, 95%CI 7.77 to 10.47, P<0.01) and working memory (SMD=1.87, 95%CI 1.07 to 2.67, P<0.01) in the VitD group of patients with cognitive impairment were all better than those in the control group. However, the overall cognitive function and working memory of the non-cognitive impairment population were not significantly different compared with the control group. In terms of language fluency and language memory, there was no significant difference between the VitD group and the control group. In terms of the executive functions, at the intervention time of> 6 months, the VitD and control groups were statistically significant (SMD=0.15, 95%CI 0.01 to 0.28, P=0.03). Conclusion Current evidence suggests that VitD supplementation can effectively improve the overall cognitive function and working memory of patients with cognitive impairment, and has a positive effect on executive function at an intervention time of >6 months. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusion.
Objective To analyze the characteristic and temporal trend in mortality and disease burden of Alzheimer’s disease (AD) and other forms of dementia in Guangzhou from 2008 to 2019, and estimate the disease burden attributable to smoking to provide evidence for promoting local health policy of prevention and intervention of dementia. Methods Based on the data of Guangzhou surveillance point of the National Mortality Surveillance System (NMSS), the crude mortality, standardized mortality, years of life lost (YLL) of AD and other dementia were calculated. The indirect method was used to estimate years lived with disability (YLD) and disability-adjusted life years (DALY).The distribution and changing trends of the index rates were compared from 2008 to 2019 using Joinpoint Regression Program. Based on the data of Guangzhou Chronic Disease and Risk Factors Monitoring System in 2013, the indexes of disease burden of AD and other forms of dementia attributable to smoking in 2018 was calculated. Results The standardized mortality rate, YLL rate, YLD rate and DALY rate of AD and other forms of dementia in Guangzhou increased from 0.45/100 000, 0.05‰, 0.02‰ and 0.07 ‰ in 2008 to 1.28/100 000, 0.15‰, 0.07‰ and 0.22‰ in 2019, respectively. The average annual changing trend was statistically significant (AAPC=11.30%, 13.09%, 13.09%, 13.09%, P<0.001）. In most years, the mortality and disease burden of women were higher than those of men, but men had higher growing trend than women in standardized mortality rate, YLL rate, YLD rate and DALY rate from 2008 to 2019, with a slower growing speed after the year 2012.The disease burden of dementia attributable to smoking in men was significantly higher than that in women. Conclusion The mortality and disease burden of AD and other forms of dementia in Guangzhou have dramatically increased over the past twelve years. Intervention against modifiable factors such as smoking, and prevention and screening for dementia in key populations should be strengthened. Support policies for dementia care management should be adopted to reduce the disease burden caused by premature death and disability.
ObjectiveTo systematically review the data of peripheral inflammatory markers in patients with Alzheimer’s disease (AD) and vascular dementia (VaD) to further indicate pathogenesis and antidiastole.MethodsPubMed, EMbase, The Cochrane Library, CNKI, WanFang Data and VIP databases were electronically searched to collect studies on peripheral inflammatory markers in patients with AD and VaD from inception to July 2020. Two reviewers independently screened literature, extracted data, and assessed risk of bias of included studies, and meta-analysis was performed by using Stata 15.1SE software.ResultsA total of 30 studies involving 2 377 patients were included. The results of meta-analysis showed that the IL-6 level was higher in VaD group than that in AD group (SMD=?0.477, 95%CI ?0.944 to ?0.009, P=0.046). However, there were no statistical difference in peripheral IL-1β (SMD=?0.034, 95%CI ?0.325 to 0.257, P=0.818), TNF-α (SMD=0.409, 95%CI ?0.152 to 0.970, P=0.153) or CRP (SMD=0.277, 95%CI ?0.228 to 0.782, P=0.282) levels.ConclusionsThese findings suggest that IL-6 may be sensitive markers to distinguish AD from VaD. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify the conclusions.
Objective To generate eukaryotic expression vector of pcDNA3.1-β-site amyloid precursor protein cleaving enzyme (BACE) and obtain its transient expression in COS-7 cells. Methods A 1.5 kb cDNA fragment was amplified from the total RNA of the human neuroblastoma cells by the RT-PCR method and was cloned into the plasmid pcDNA3.1. The vector was identified by the double digestion with restriction enzymes BamHI and XhoI and was sequenced by the Sanger-dideoxy-mediated chain termination. The expression of the BACE gene was detected by immunocytochemistry. Results The results showed that the cDNA fragment included 1.5 kb total coding region. The recombinant eukaryotic cell expression vector of pcDNA3.1-BACE was constructed successfully, and the sequence of insert was identical to the published sequence. The COS-7 cells transfected with the pcDNA3.1BACE plasmid expressed a high level of the BACE protein in the cytoplasm. Conclusion The recombinant plasmid pcDNA3.1-BACE can provide a very useful tool for the research on the cause of Alzheimer’s disease and lay an important foundation for preventing Alzheimer’s disease.
ObjectivesTo systematically review the efficacy and safety of butylphthalide soft capsule with routine treatment for Alzheimer’s disease (AD).MethodsDatabases including CNKI, WanFang Data, VIP, CBM, PubMed, EMbase, and The Cochrane Library were electronically searched from September 2002 to July 2018 to collect randomized controlled trials of butylphthalide soft capsule with routine treatment for Alzheimer’s disease. The trial was screened based on inclusion and exclusion criteria, and the methodological quality of the included trial was assessed. Meta-analysis was then performed by Revman 5.3 software.ResultsA total of 8 studies involving 576 patients were included. The butylphthalide soft capsule group included 283 patients and the control group included 293 patients. The result of meta-analysis showed that butylphthalide soft capsule with routine treatment (Donepezil hydrochloride or Memantine or EGb761) significantly improved the score of mini-mental state examination (MMSE) (MD=3.19, 95% CI 2.69 to 3.69, P<0.001) and clinical efficacy (RR=1.36, 95%CI 1.21 to 1.53, P<0.001). There was no significant difference in number of adverse events between the butylphthalide group and the control group (RR=1.13, 95%CI 0.77 to 1.67, P=0.52).ConclusionsBased on the routine treatment, combining with butylphthalide soft capsule can further facilitate cognitive function of AD and improve clinical efficacy. At the same time, no increase in adverse reactions has been found. However, due to the low quality of the included studies, more high quality randomized controlled trials are required to verify the results.
ObjectiveTo systematically review the diagnostic value of miRNAs for Alzheimer’s disease (AD).MethodsPubMed, Web of Science, EMbase, The Cochrane Library, CNKI, WanFang Data, VIP, and CBM databases were electronically searched to collect diagnostic tests of miRNAs for AD from inception to October 31, 2020. Two researchers independently screened literature, extracted data, and assessed the risk of bias of the included studies. RevMan 5.3 and Stata 14.0 software were used for meta-analysis. ResultsA total of 22 studies involving 4 006 subjects were included. The meta-analysis results showed that the pooled sensitivity, specificity, positive and negative likelihood ratios, diagnostic odds ratio, and the areas under the working characteristic curve of miRNA in AD diagnosis were 0.83 (95%CI 0.79 to 0.87), 0.80 (95%CI 0.76 to 0.83), 4.07 (95%CI 3.37 to 4.92), 0.21 (95%CI 0.17 to 0.27), 19.20 (95%CI 12.96 to 28.48) and 0.88 (95%CI 0.85 to 0.90), respectively. ConclusionThe current evidence shows that miRNAs have a high diagnostic value for AD. However, because of the limited quality and quantity of the included studies, more high-quality studies are required to verify the above conclusion.
Caveolin-1 (Cav-1) protein plays a very important role in the central nervous system, and is closely related to Alzheimer’s disease (AD). Through literature review, this article summarizes the present research status of Cav-1 protein in the field of AD from three aspects: the relationship between Cav-1 gene and AD; the relationship of Cav-1 protein with learning and memory; the relationship of Cav-1 protein with amyloid β-protein and Tau protein. And the aim of this paper is to provide a new thought and evidence for exploring the mechanism of AD via Cav-1 protein.
Objective To evaluate the relationship between genetic polymorphism of ApoE and Alzheimer’s disease in Chinese population. Methods Such databases as PubMed, EBSCO, CNKI, CBM, and WangFang Data were searched from their establishment to December 2010 to collect the literature about the relationship between genetic polymorphism of ApoE and Alzheimer’s disease in Chinese population. RevMan 5.0 was adopted to conduct consistency check and data merging, and to evaluate publication bias. Results ApoEε4 was the risky allele (Plt;0.05) in Chinese population, and its pooled odds ratios and 95%CI was 3.53 (2.49 to 5.00). ApoEε3 was the protective alleles (Plt;0.05) in Chinese population, and its pooled odds ratios and 95%CI was 0.52 (0.40 to 0.68). ApoEε4/ε4, ApoEε4/ε3, and ApoEε4/ε2 were the risky genotypes (all Plt;0.05) in Chinese population, and their pooled odds ratios and 95%CI were 10.17 (4.25 to 24.19), 2.57 (2.04 to 3.25), and 1.94 (1.13 to 3.34), respectively. ApoEε3/ε3 was the protective genotype (Plt;0.05) in Chinese population, and its pooled odds ratios and 95%CI was 0.67 (0.57 to 0.77). Conclusion In Chinese population, some ApoE alleles and genotypes are associated with Alzheimer’s disease.
Objective To evaluate the efficacy and safety of memantine in the treatment of Alzheimer’s disease (AD). Methods The randomized controlled trials (RCTs) about memantine vs. donepezil for patients with AD from January 1989 to July 2011 were searched in CBM, CNKI, WanFang Data, MEDLINE, OVID, EMbase and The Cochrane Library. Two reviewers independently screened the literatures, extracted the data, and evaluated the methodological quality. Then meta-analyses were conducted by using RevMan 5.0 software. Results The total 12 RCTs were included. Among the 2 716 patients involved, 1 459 were in the memantine group, while the other 1 302 were in the donepezil group. The results of meta-analyses showed that the efficacy of the memantine group was superior to that of the donepezil group in MMSE (MD=0.53, 95%CI 0.21 to 0.85, P=0.001), CIBIC-Plus (MD= –0.19, 95%CI –0.31 to –0.07, P=0.002), NPI (MD= –2.9, 95%CI –4.57 to –1.22, P=0.000 7) and SIB (MD=3.12, 95%CI 0.57 to 5.67, P=0.02), with significant differences; but the efficacy of the two groups was similar in ADCS-ADL19 (MD=0.29, 95%CI –0.03 to 0.60, P=0.07). There was no significant difference between the two groups in incidence of side effects (RR=1.14, 95%CI 0.94 to 1.38, P=0.17), but the tolerability of the memantine group was much better (RR=0.78, 95%CI 0.63 to 0.97, P=0.03). Conclusion Based on the current studies, memantine is superior to donepezil in treating Alzheimer’s disease (AD) at present. Although the side effects are similar to donepezil, memantine has much better intolerability and is considered to be safe and effective. For the quality restrictions and possible publication bias of the included studies, more double blind RCTs with high quality are required to further assess the effects.
