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Objective@#To investigate the correlation of functional connectivity (FC) and the integrity of connective fibres between hippocampus and thalamus in Alzheimer′s disease(AD) and amnestic mild cognitive impairment (aMCI).@*Methods@#Both resting-state functional magnetic resonance imaging (rs-fMRI) and diffusion tensor imaging (DTI) data of 40 AD patients, 37 aMCI patients and 41 normal control subjects matching with age and educational level were collected. These subjects were all recruited from outpatient Department of Neurology in the Second Medical Center of Chinese PLA General Hospital, as well as poster, from May 2016 to January 2018. The FC strength between bilateral hippocampus and thalamus, as well as the parameters representing integrity of connective fibres, including fractional anisotropy (FA) and mean diffusivity(MD),were analyzed. Also, the correlations between FC strength and FA or MD strength were analyzed in the study.@*Results@#Compared to that of normal control subjects, the FC strength between billateral hippocampus and thalamus in patients with AD, aMCI were not significantly different(P>0.05). The integrity of bilateral connective fibres between hippocampus and thalamus were damaged in AD patients when compared to normal control subjects(P<0.01). A positive correlation of connective fibres integrity with FC strength between hippocampus and thalamus was found in the left side(r=0.25,P<0.05) but rather in the right side.@*Conclusion@#In AD and aMCI patients, structural connectivity between left hippocampus and thalamus affects the functional connectivity between them.
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Objective@#To verify the criteria validity and effectiveness of the QCSS-E for screening of mild cognitive impairment (MCI) and early dementia with Alzheimer's type (DAT) among the elderly in community.@*Methods@#With stratified convenient sampling, 1 298 elderly aged 55 and over recruited from Wuxi community, who finished the clinical interviews, laboratory examination and psychological tests such as QCSS-E, ADL, MMSE, ADAS-cog, CDR, and Core Neuropsychological Test.Then they were divided into health control group(HC), MCI group and DAT group by the diagnostic criteria of Peterson’s MCI and DSM-5 AD dementia.The criteria validity and screening efficacy of QCSS-E were verified and the optimal cut off value for detecting MCI and DAT were explored.@*Results@#There were statistically significant differences in age, education level, marital status, family structure, occupation, and scores of MMSE, ADAS-cog, CNT, and QCSS-E total score and domain scores among three groups (all P<0.01). The total score and every domains score of QCSS-E were significantly correlated with test scores such as MMSE, ADAS-cog and CNT (all P<0.01). Using the total QCSS-E score to discriminate MCI from health control, the area under the curve (AUC) was 83.5%. When the cut off value was 74.5, the accuracy rate of classification was the highest (75.0%). Using the total QCSS-E score to discriminate DAT from health control, the AUC was 83.5%. When the cut off value was 64.5, the accuracy rate of classification was the highest (94.2%).@*Conclusion@#The QCSS-E has better criteria validity and higher effectiveness in screening MCI and DAT.
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Dual task walking (DTW) refers to the task of performing another attentional demand while walking naturally. It is quite common in our daily life, such as having a conversation while walking, or taking a call while crossing the street. People can simultaneously perform dual tasks normally. However, the performance of dual tasks will decline when the gait is impaired or cognitive dysfunction occurs.Neurodegenerative disease (NDD) is mainly characterized by motor and cognitive dysfunction, which seriously affects patients' ability of daily living activities. In recent years, studies on DTW in patients with NDD have found that decreased performance of DTW may be a feature of NDD patients, which may have important clinical value for early identification of NDD and predict disease progression. In the future, effective DTW training may improve the patients' ability of daily living activities, and it is important for the rehabilitation of NDD patients. This article mainly reviews the definition, common methods and mechanisms of DTW, as well as the clinical research findings and applications of DTW in patients with NDD, and provides theoretical basis for further clinical research.
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Objective@#To observe the correlation between serum trace elements and homocysteine (Hcy) levels and cognitive function in elderly patients with Alzheimer's disease(AD).@*Methods@#From January 2017 to December 2018, 65 patients with AD who were diagnosed and treated in the Department of Internal Medicine of the Seventh People's Hospital of Wenzhou were selected in this study.In the same period, 50 healthy people in the physical examination center of our hospital were selected as the control group.MMSE scale was used to evaluate the cognitive status of patients.The score of MMSE 27-30 belongs to normal cognitive function.The score of MMSE<27points is cognitive dysfunction.The score of MMSE 21-26points is mild cognitive dysfunction.The score of MMSE 10-20points is moderate cognitive dysfunction.The score of MMSE 0-9points is severe cognitive dysfunction.The levels of Hcy, serum copper, serum iron and serum zinc in all subjects were detected and analyzed.The normal value of copper is 7.12-33.8 μmol/L.The normal value of zinc is 67.72-111.30 μmol/L.The normal value of iron is 7.27-9.85 μmol/L.@*Results@#The serum copper level of the control group was significantly lower than that of the moderate and severe patients, which of the mild patients was significantly lower than that of the moderate and severe patients(F=12.796, P=0.003). The level of serum iron in the control group was significantly higher than that in the mild group, and there was statistically significant difference between the moderate group and severe group (F=3.332, P=0.021). The serum zinc level in the control group was significantly higher than that in the mild, moderate and severe patients (F=123.618, P=0.000). There were statistically significant differences in serum zinc concentration between mild and moderate patients and severe patients (F=26.3672, P=0.0000). The serum zinc concentration in moderate patients was significantly lower than that in severe patients (F=12.375, P=0.009). The levels of Hcy in mild, moderate and severe patients in the study group were significantly higher than those in the control group, and the difference was statistically significant(F=6.549, P=0.020). Serum copper concentration was positively correlated with MMSE score (r=10.100, P=0.000). The higher the serum copper concentration, the higher the MMSE score, the more serious the cognitive impairment.The serum zinc and iron levels in patients were negatively correlated with the MMSE score (r=6.039, P=0.037). The lower the serum zinc concentration, the higher the scores of MMSE scale and the lighter the degree of cognitive impairment.@*Conclusion@#The changes of serum iron, zinc and copper levels in patients with AD are closely related to cognitive function.Serum copper is positively correlated with the severity of the disease, while serum zinc is negatively correlated with iron and severity of the disease.
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Objective@#To investigate the effects of cerebral cavernous malformation 3 (CCM3) gene knockout on the lead exposure-induced blood-brain barrier malfunction in mice brain, and the relationship between CCM3 knockout and the Alzheimer's disease (AD).@*Methods@#Wide type (WT) mice and CCM3+/- mice were divided into 4 groups, control group and lead exposed group in WT as well as CCM3+/- mice. Lead exposed groups were treated with 0.05% lead acetate in drinking water for 12 weeks, while control group drink deionized water freely. Blood lead and brain lead levels in each group were detected by graphite furnace atomic absorption spectrometry. The brain tissue of each group was made into paraffin sections, whose morphology were observed by HE staining. The expression of Aβ1-42 in brain tissue was detected by immunohistochemistry and the brain capillaries were labeled by VRGFR2. The protein expression of Claudin-5, ZO-1, and p-Tau was detected by Western blot. The brain tissue RNA was extracted and the relative expression of LRP-1 mRNA was detected by qRT-PCR.@*Results@#The levels of blood lead WT (216.07±84.16) and CCM3+/- (189.64±101.86) μg/L in lead exposed group were higher than those in control group WT (19.52±11.46) and CCM3+/- (11.79±8.20) μg/L, the difference was statistically significant (t=4.18, P=0.006; t=3.79, P=0.016). The levels of brain lead WT (1.78±0.69) and CCM3+/- (1.74±0.66) μg/L were higher than those in control group WT (1.06±0.87) and CCM3+/- (0.97±0.64) μg/L, the difference was statistically significant (t=3.67, P=0.018; t=3.88, P=0.015). The HE staining showed no obvious lesions in the brain of each group of mice. The results of immunohistochemistry showed that there was no Aβ1-42 deposition in the brain of mice in each group. The numbers of microvessels in the brain of CCM3+/- mice in the lead exposed group were decreased. Compared with the relative expression levels of Claudin-5 (WT: 1.30±0.03, CCM3+/-: 1.07±0.08) in control group mice brain, the relative expression of Claudin-5 (WT: 0.96±0.04, CCM3+/-: 0.59±0.01) was decreased with statistical significance (F=199.27, P<0.001). The relative expression level of LRP-1 gene mRNA in brain of lead exposed group (WT: 0.32±0.10, CCM3+/-: 0.06±0.01) was higher than that of unexposed group (WT:1.00±0.06, CCM3+/-:2.12±0.18), the difference was statistically significant (F=288.29, P<0.001). The relative expression level of LRP-1 gene mRNA in brain of CCM3+/- mice exposed to lead was lower than that of WT mice ((0.06±0.01)vs(0.32±0.10), t=26.90, P<0.001).@*Conclusion@#The mice did not show significant AD-like lesions under low-does lead exposure, but resulted in early damage of brain blood-brain barrier and early changes of AD-like lesions in mice, with CCM3+/- mice being sensitive to lead exposure stronger than that of WT mice, suggesting that deletion of CCM3 gene may be one of the potential risk factors for accelerating the development of AD in mice exposed to lead.
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Along with the development of periodontal medicine, there is a growing number of evidence showing that periodontitis could influence systemic health. Periodontitis is a chronic inflammatory disease caused by microbial infection mediated by dental plaque. Periodontal pathogenic microorganisms and its toxic products can disseminate through the blood stream or may cause the host immune response, which may lead to pathological changes of cerebral vessels and brain tissues to establish connection with Alzheimer's disease (AD). AD is a progressive neurodegenerative disease characterized by progressive memory loss, language and cognitive dysfunction. This article reviewed the association between chronic periodontitis and AD.