Clinical features of long segmental myelopathy caused by nitrous oxide / 北京大学学报(医学版)

OBJECTIVE@#To analyze the clinical and imaging characteristics of the neurological damage caused by nitrous oxide (N2O).@*METHODS@#In the study, 10 patients in the Department of Neurology of China-Japan Friendship Hospital from October 2015 to February 2018 were retrospectively analyzed for the demographic data, the history of inhaled N2O, clinical features, blood examination, electrophysiological examination, spinal magnetic resonance imaging and therapeutic efficacy profiles.@*RESULTS@#The male-to-female ratio was 4:6 and it presented with an age-of-onset 17-26 years [the average age: (20.80±3.12) years]. The time from inhaled N2O to onset was 1 month to 1 year [the average time: (6.95±4.19) months]. Paralysis in all the patients and numbness in 9 patients were the main clinical features, while positive Lhermitte's sign in 3 patients, urinary and defecation disturbance in 4 patients were also found. Blood examination indicated anemia in 2 patients, giant cell anemia in 1 case and small cell hypochromic anemia in 1 case. 3 cases had been treated with vitamin B12 in an external hospital, and the other 7 cases had abnormal increase in homocysteine levels. Electrophysiological examinations showed sensory and motor nerve involvement in 9 patients, and motor nerve involvement in 1 patient. The severity of lower extremity lesion was significantly heavier than that of upper extremity. Spinal magnetic resonance imagings showed that long segmental lesions were present in the cervical spinal cord of all the patients, 3 cases with long segmental lesions of the thoracic cord and 2 cases with spinal cord swelling. In 6 cases, the horizontal axis had an "inverted V-type" T2 high signal, 1 case was classified as "crescent", and 3 cases were "eight-shaped". The symptoms in these 10 cases were alleviated in varying degrees after stopping the inhalation of nitrous oxide, actively supplementing high doses of vitamin B12 and doing early rehabilitation exercises.@*CONCLUSION@#Myelopathy with nitrous oxide presents as paralysis and numbness in limb extremities. In imaging, cervical spinal cord damage is common, accompanied by thoracic spinal cord damage. The horizontal axis is more common in the "inverted V-type". Treatment with high doses of vitamin B12 is effective.

Amide proton transfer magnetic resonance imaging of Alzheimer's disease at 3.0 Tesla: a preliminary study / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Amide proton transfer (APT) imaging has recently emerged as an important contrast mechanism for magnetic resonance imaging (MRI) in the field of molecular and cellular imaging. The aim of this study was to evaluate the feasibility of APT imaging to detect cerebral abnormality in patients with Alzheimer's disease (AD) at 3.0 Tesla.</p><p><b>METHODS</b>Twenty AD patients (9 men and 11 women; age range, 67-83 years) and 20 age-matched normal controls (11 men and 9 women; age range, 63-82 years) underwent APT and traditional MRI examination on a 3.0 Tesla MRI system. The magnetic resonance ratio asymmetry (MTR asym ) values at 3.5 ppm of bilateral hippocampi (Hc), temporal white matter regions, occipital white matter regions, and cerebral peduncles were measured on oblique axial APT images. MTR asym (3.5 ppm) values of the cerebral structures between AD patients and control subjects were compared with independent samples t-test. Controlling for age, partial correlation analysis was used to investigate the associations between mini-mental state examination (MMSE) and the various MRI measures among AD patients.</p><p><b>RESULTS</b>Compared with normal controls, MTR asym (3.5 ppm) values of bilateral Hc were significantly increased in AD patients (right 1.24% ± 0.21% vs. 0.83% ± 0.19%, left 1.18% ± 0.18% vs. 0.80%± 0.17%, t = 3.039, 3.328, P = 0.004, 0.002, respectively). MTR asym (3.5 ppm) values of bilateral Hc were significantly negatively correlated with MMSE (right r = -0.559, P = 0.013; left r = -0.461, P = 0.047).</p><p><b>CONCLUSIONS</b>Increased MTR asym (3.5 ppm) values of bilateral Hc in AD patients and its strong correlations with MMSE suggest that APT imaging could potentially provide imaging biomarkers for the noninvasive molecular diagnosis of AD.</p>

Neuropsychiatric symptoms in dementia and elderly people in the community: results from the Beijing Dementia Cooperative Study / 中华流行病学杂志

<p><b>OBJECTIVE</b>To determine the prevalence of neuropsychiatric symptoms in dementia and normal elderly people living in the Chinese community of Beijing.</p><p><b>METHODS</b>A cross-sectional study derived from the Beijing Dementia Cooperative Study was carried out a population survey was carried out on a total of 1540 participants aged 65 years and older living in Beijing city and rural areas. All the individuals and 373 demented elderly people completed a series of neuropsychological examination and the Neuropsychiatric Inventory (NPI).</p><p><b>RESULTS</b>Among the dementia participants, 49.33% had exhibited neuropsychiatric symptoms (35.66% rated as clinically significant), in which 80.4% reported 2 or more disturbances, with depression (23.86%), apathy (21.72%) and anxiety (20.38%) being most common. Of the 1540 normal individuals, 18.25% of them exhibited neuropsychiatric symptoms (6.49% rated as clinically significant), in which 53% reported 2 or more disturbances, with sleepless (10%), depression (8.9%) and anxiety (6.97%) being the most common.</p><p><b>CONCLUSION</b>To our knowledge, this was the first multi-center study on neuropsychiatric disturbances in dementia and cognitive normal elderly people. Neuropsychiatric symptoms occurred mainly in persons with dementia and of clinical severity. Though the neuropsychiatric disturbances reported in cognitive normal individuals were lower and less serious compared to dementia, they should not be neglected. These finding suggested that a screening programme focusing on identifying these symptoms should be included in the physician's diagnostic tools for dementia.</p>

Clinical study on mild cognitive impairment converting to dementia / 中华神经科杂志

Objective To study the natural history of mild cognitive impairment (MCI) progress to dementia and to evaluate the efficacy of acetylcholinesterase inhibitor (AChEI) donepezil on MCI.Methods Ninty-eight patients with MCI including amnestic MCI and non-amnestic MCI were retrospectively analyzed. The patients with donepezil or not were separately divided to two groups while they were matched by sex, age,degree of MCI and possession of the ApoE?4 allele.The rate of conversion from MCI to dementia, measured with the Mini-Mental State Examination (MMSE),Alzheimer's Disease Assessment Scale- Cognitive section(ADAS-Cog) and Wechsler Memory Scale-Revised (WMS-R),was compared between the two groups.Results In aMCI group,the rate of conversion dropped by 15.1% and 8.3% (P0.05).Conclusion Donepezil could postpone the conversion of MCI to dementia.