| First section:White matter changes in mild cognitive impairment and A diffusion tensor imaging studyBackgroud:Due to the emergence and application of new techniques of diffusion tensor imaging, changes in the integrity of white matter (WM) can now be detected. The role of changes in the WM of a brain with Alzheimer disease (AD) is not known. The aim of the current study was to investigate the association of the integrity of WM with cognitive performance, to detect the most sensitive marker, and to find the region of interest (ROI) that is infected earliest.Methods:The study was designed to evaluate the microstructural integrity of WM and the changes in cognitive impairment among elderly Han Chinese in normal patients, amnestic patients with mild cognitive impairment (MCI), and patients with AD using diffusion tensor imaging (DTI) techniques, and to investigate the relationship between WM abnormalities in the ROI. The study was also designed to evaluate cognitive impairment during the progression of AD using several neuropsychological assessments. Forty-seven subjects were divided into three groups;17patients with Alzheimer Disease (AD),14patients with mild cognitive impairment (MCI), and16Normal control subjects (NC), underwent diffusion-tensor imaging performed with a1.5-T magnetic resonance system. The mean apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of several WM regions were determined. Neuropsychological data including the Mini-Mental State Exam1and the Alzheimer's Disease Assessment Scale (ADAS)" were also assessed.Results:Compared to the NC group, the AD group showed lower FA values in bilateral frontal lobe WM (p<0.01). Compared to the NC group, the AD group had significantly higher ADC values in frontal lobe WM and the anterior and posterior cingulate fibers (p<0.01, for all). Compared to the MCI group, the AD group had significantly increased ADC values in right anterior cingulated fibers and left posterior cingulate fibers (p<0.05for all).The results shows the memory factor scores are associated with the decreased FA in the ROI of bilateral caudate nucleus, frontal lobe, left occipital lobe, left parietal, splenium of corpus callosum, left temporal lobe, right anterior cingulated. Practice factor was associated with the decreased FA valum of the caudate nucleus, occipital lobe, left parietal, splenium of corpus callosum, right anterior cingulate gyrus; the practice ability factor was associated with the decreased FA value of the right caudate nucleus, the left occipital lobe, left parietal cortex, left anterior cingulate cortex. Mood factor is associated with the decreased FA of the left caudate nucleus, frontal lobe; Agitation factor was associated with the decreased FA of the caudate nucleus, the right occipital lobe, right anterior cingulate gyrus. Psychotic manifest factor was associated with the FA of the left posterior cingulate gyrus.Memory scores were significantly associated with the increased ADC value of bilateral caudate, right frontal lobe, the genu of CC, left occipital lobe, the left parietal lobe, temporal lobe, the anterior cingulated; the language factor was significantly associated with the increased ADC valum of the bilateral caudate nucleus, frontal lobe, the genu of CC, right occipital lobe, temporal lobe, right thalamus, anterior cingulate gyrus; The practice ability factor was significantly associated with the increased ADC value of the caudate nucleus, frontal, the genu of CC, left parietal lobe, temporal lobe, left anterior cingulate gyrus; the agitation factor was significantly associated with bilateral caudate nucleus, frontal lobe, the genu of CC, the left occipital lobe, right thalamus, temporal lobe, right anterior cingulate gyrus; the psychosis factor score was significantly associated with the ADC valum of the frontal lobe, right thalamus. The mood factor was not associated with the ADC valum of any ROI.Conclusion:The results indicated that DTI can detect microstructural WM abnormalities in elderly Han Chinese patients with AD and amnesic MCI. Detecting ADC values in posterior cingulate regions may be helpful with the diagnosis of AD and MCI. In the detection of the microstructural integrity of WM in the MCI and AD groups, ADC values seem to be more sensitive than FA values. The FA and ADC values of CC maybe not help to detect early phase AD.Detecting the FA valum in bilateral caudate nucleus, frontal lobe, left occipital lobe, left parietal, splenium of corpus callosum, left temporal lobe, right anterior cingulate region and the ADC valum of bilateral caudate, right frontal, the genu of CC, left occipital lobe, left parietal lobe the anterior cingulate cortex, temporal lobe, maybe helpful to understand the impairment of cognitive function in a-MCI and AD. Objective:The study was designed to study the writing disorders of Alzheimer disease (AD) and amnestic mild cognitive impairement (a-MCI) in patients of Chinese patients. The correlation between the writing disorder and other cognitive domain impairment was also been studied. By neuropsychological assessments, the similarities and differences of the aphasia manifestation between han-speaking and English-speaking patients were discussed.Methods:17patients with AD,14patients with a-MCI, and16normal control subjects (NC), were evaluated using the MMSE, Alzheimer Disease Assessment Scale (ADAS) and the Aphasia Battery of Chinese (ABC) in the First affiliated Hospital of Peking University. The scores the factors of ABC were compared with that of ADAS. The results of writing tests of patients were analyzed. The different features between Chinese and English aphasia were discussed.Results:There are no correlation between the scores of factors of writing test with the age, gender, educated level, diabetes and high blood pressure. The scores of writing factors showed significant correlation with the scores of MMSE and ADAS factors (p<0.01). There were no significant correlation between the scores of writing factors and that of the factors of'mood'and "metal performance'. The scores of writing subtests of AD gorup were significantly different comparing with that of NC group and A-MCI group. There are no correlation between the NC group and A-MCI group in writing scores. The writing disorder of han-speaking AD patients displayed several language menifestations.Conclusion:The writing ability of han-speaking AD and A-MCI patients is significantly correlated with the scores of ADAS cognition subtest. This suggested the impairment of writing ability is greatly associated with the impairment of cognition. Dysgraphic difficulties can be detected during different stages of dementia, it maybe the most common phenomenon in writing disorders in han-speaking patients. While most of the studies have demonstrated that lexical spelling (writing of familiar regular, irregular, or ambiguouswords through an orthographic output lexicon) is early effect in English-speaking in AD. While lexical spelling is not exist in Chinese. The writing disorders in han-speaking AD patients showed an unique manifestation.This is a difference between Chinese writing AD patients with English writing AD patients.
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