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81.
Brain Gray and White Matter Volume Loss Accelerates with Aging in Chronic Alcoholics: A Quantitative MRI Study 总被引:15,自引:0,他引:15
Adolf Pfefferbaum Kelvin O. Lim Robert B. Zipursky Daniel H. Mathalon Margaret J. Rosenbloom Barton Lane Chung Nim Ha Edith V. Sullivan 《Alcoholism, clinical and experimental research》1992,16(6):1078-1089
Magnetic resonance imaging (MRI) was used to study in vivo the brains of 49 patients with chronic alcoholism, 3 to 4 weeks post-withdrawal, and 43 normal healthy controls, all right-handed male veterans between the ages of 23 and 70 years. MRI scans were analyzed using a semi-automated procedure, which allowed the subcortical regions to be segmented into cerebrospinal fluid (CSF) and brain tissue and the cortical regions to be segmented into CSF, gray matter, and white matter. An age regression model was used to examine the effects of alcohol on brain structure, over and above that expected from the normal aging process. The alcoholics exhibited decreased tissue and increased CSF after correcting for aging. In the cortex, there was significant loss of both gray matter and white matter volume. In this sample of alcoholics, no particular cortical region was preferentially affected or spared. Furthermore, brain tissue volume loss increased with advanced age in the alcoholics. In this group of alcoholics there was no relationship between length of illness and age, i.e., the younger alcoholics had as heavy alcohol use histories as did the older alcoholics. Thus, the increased brain tissue loss with advanced age is interpreted as evidence for age-related increase in brain vulnerability to chronic alcohol abuse. 相似文献
82.
83.
Hee Jin Kim Byoung Seok Ye Cindy W. Yoon Hanna Cho Young Noh Geon Ha Kim Yae Seul Choi Jung-Hyun Kim Seun Jeon Jong Min Lee Jae Seung Kim Yearn Seong Choe Kyung Han Lee Sung Tae Kim Changsoo Kim Dae Ryong Kang Chang-Seok Ki Jae Hong Lee David J. Werring Michael W. Weiner Duk L. Na Sang Won Seo 《Neurobiology of aging》2013
The relationship between the apolipoprotein E ?4 allele (APOE4) and factors associated with vascular cognitive impairment (VCI) is unclear. We aimed to examine the effects of APOE4 on brain amyloid beta using Pittsburg compound B (PiB) and subcortical cerebrovascular disease, as assessed by lacunes and white matter hyperintensities (WMH) in subcortical VCI (SVCI) patients. We recruited 230 subjects with normal cognition, 111 subjects with cognitive impairment due to clinically defined Alzheimer’s disease (ADCI), and 134 subjects with clinically defined SVCI. A PiB retention ratio greater than 1.5 was considered to be PiB positive. Logistic regression analysis was performed to investigate whether APOE4 increased the risk for each cognitive impairment group. Multiple linear regression analysis was performed to investigate whether APOE4 was associated with brain amyloid beta, lacunes, and WMH. APOE4 did not increase the risk of PiB(−) SVCI (odds ratio [OR], 1.50; 95% confidence interval [CI], 0.79–2.84), whereas APOE4 increased the risk of PiB(+) SVCI (OR, 4.52; 95% CI, 1.70–11.97) and PiB(+) ADCI (odds ratio, 4.84; 95% CI, 2.54–7.91). In SVCI patients, APOE4 was positively associated with PiB retention ratio, whereas APOE4 was not associated with the number of lacunes or with WMH volume. Our results suggest that amyloid beta burden can occur in patients with and without subcortical cerebrovascular disease, and that it is associated with APOE4. However APOE4 might be independent of subcortical cerebrovascular disease. 相似文献
84.
Colin J. Mahoney Ian B. Malone Gerard R. Ridgway Aisling H. Buckley Laura E. Downey Hannah L. Golden Natalie S. Ryan Sebastien Ourselin Jonathan M. Schott Martin N. Rossor Nick C. Fox Jason D. Warren 《Neurobiology of aging》2013
The primary progressive aphasias (PPA) are a heterogeneous group of language-led neurodegenerative diseases resulting from large-scale brain network degeneration. White matter (WM) pathways bind networks together, and might therefore hold information about PPA pathogenesis. Here we used diffusion tensor imaging and tract-based spatial statistics to compare WM tract changes between PPA syndromes and with respect to Alzheimer's disease and healthy controls in 33 patients with PPA (13 nonfluent/agrammatic PPA); 10 logopenic variant PPA; and 10 semantic variant PPA. Nonfluent/agrammatic PPA was associated with predominantly left-sided and anterior tract alterations including uncinate fasciculus (UF) and subcortical projections; semantic variant PPA with bilateral alterations in inferior longitudinal fasciculus and UF; and logopenic variant PPA with bilateral but predominantly left-sided alterations in inferior longitudinal fasciculus, UF, superior longitudinal fasciculus, and subcortical projections. Tract alterations were more extensive than gray matter alterations, and the extent of alteration across tracts and PPA syndromes varied between diffusivity metrics. These WM signatures of PPA syndromes illustrate the selective vulnerability of brain language networks in these diseases and might have some pathologic specificity. 相似文献
85.
none 《Journal of histotechnology》2013,36(2):125-127
AbstractThis paper describes a rapid protocol for iliac crest biopsies with embedding in LR White plastic to facilitate diagnosis of osteomalacia. Sections were cut and stained for light and electron microscopy using traditional staining methods with minor modifications. Total processing time was within three days. (The J Histotechnol 13:125, 1990) 相似文献
86.
《Gait & posture》2021
BackgroundSocial anxiety caused by the presence of an evaluator can impair balance performance in older women. However, it is unknown whether co-performing balance tasks with a partner mitigates this effect.Research questionDoes the presence of a partner mitigate the effect of social anxiety on static and dynamic balance assessment in older women?MethodsTwenty-one older women (mean age 66.5 (SD = 5.2) years) performed nine balance tasks under three conditions: (a) Alone (no evaluator present); (b) Evaluator (male evaluator present); (c) Partner (evaluator + performing tasks in parallel with partner). Participants were split into two groups post-hoc: Affected (n = 10) and Unaffected (n = 11), based on their emotional response to the presence of the evaluator (increased self-reported anxiety and fear).ResultsThe affected group took a longer time to complete tandem walking with eyes open in the Evaluator vs. Alone condition, but not in the Partner condition. Both groups increased anterior-posterior trunk angular velocity during tandem walking with eyes closed in the Evaluator vs. Alone condition, but not in the Partner condition.SignificanceSocial anxiety impairs the balance performance of older women, particularly in those most affected by the evaluator, and during more dynamic modified gait tasks that challenge balance while walking. However, co-performing balance tasks with a partner reduced the effects of social anxiety, suggesting that social support may help to mitigate some of the potential ‘white coat’ effects experienced during clinical balance assessments. 相似文献
87.
Severe postnatal systemic infection is highly associated with persistent disturbances in brain development and neurobehavioral outcomes in survivors of preterm birth. However, the contribution of less severe but prolonged postnatal infection and inflammation to such disturbances is unclear. Further, the ability of modern imaging techniques to detect the underlying changes in cellular microstructure of the brain in these infants remains to be validated. We used high-field ex-vivo MRI, neurohistopathology, and behavioral tests in newborn rats to demonstrate that prolonged postnatal systemic inflammation causes subtle, persisting disturbances in brain development, with neurodevelopmental delays and mild motor impairments. Diffusion-tensor MRI and neurite orientation dispersion and density imaging (NODDI) revealed delayed maturation of neocortical and subcortical white matter microstructure. Analysis of pyramidal neurons showed that the cortical deficits involved impaired dendritic arborization and spine formation. Analysis of oligodendrocytes showed that the white matter deficits involved impaired oligodendrocyte maturation and axonal myelination. These findings indicate that prolonged postnatal inflammation, without severe infection, may critically contribute to the diffuse spectrum of brain pathology and subtle long-term disability in preterm infants, with a cellular mechanism involving oligodendrocyte and neuronal dysmaturation. NODDI may be useful for clinical detection of these microstructural deficits. 相似文献
88.
Anandita Pattnaik Alexandra Lim Sara Sabeti Ashley Kwon Katherine Hall Ira Lott Virginia Kimonis 《European journal of medical genetics》2021,64(9):104234
In this report, we describe an unusual case of progressive hemifacial atrophy or Parry-Romberg syndrome in a 10-year-old girl with progressive hemifacial microsomia and limb anomalies who had brain magnetic resonance imaging (MRI) findings of white matter hyper-intensities. Patients typically present with neurological manifestations such as epilepsy, facial pain, and migraines and ophthalmological symptoms in conjunction with white matter lesions. The patient demonstrated normal cognition and psychomotor development despite the presence of white matter lesions in her frontal lobe that is commonly associated with neurological symptoms. This report brings attention to the complicated relationship between facial, limb and brain imaging findings in Parry-Romberg syndrome and differentiates it from hemifacial microsomia syndrome. 相似文献
89.
Language acquisition is of central importance to child development. Although this developmental trajectory is shaped by experience postnatally, the neural basis for language emerges prenatally. Thus, a fundamental question remains: do structural foundations for language in infancy predict long-term language abilities? Longitudinal investigation of 40 children from infancy to kindergarten reveals that white matter in infancy is prospectively associated with subsequent language abilities, specifically between: (i) left arcuate fasciculus and phonological awareness and vocabulary knowledge, (ii) left corticospinal tract and phonological awareness, and bilateral corticospinal tract with phonological memory; controlling for age, cognitive, and environmental factors. Findings link white matter in infancy with school-age language abilities, suggesting that white matter organization in infancy sets a foundation for long-term language development. 相似文献
90.
Early life stress (ELS) is associated with increased risk for internalizing disorders and variations in gray matter development. It is unclear, however, whether ELS affects normative age-related changes in white matter (WM) morphology, and if such maturational differences are associated with risk for internalizing psychopathology. We conducted comprehensive interviews in a cross-sectional sample of young adolescents (N = 156; 89 F; Ages 9–14) to assess lifetime exposure to stress and objective cumulative ELS severity. We used diffusion-weighted imaging to measure WM fixel-based morphometry and tested the effects of age and ELS on WM fiber density and cross-section (FDC), and associations between WM FDC and internalizing problems. Age was positively associated with FDC in all WM tracts; greater ELS severity was related to stronger age-WM associations in several association tracts connecting the frontal lobes with limbic, parietal, and occipital regions, including bilateral superior and inferior longitudinal and uncinate fasciculi (UF). Among older adolescents with greater ELS severity, a higher UF FDC was associated with fewer internalizing problems. Greater ELS severity predicted more mature WM morphometry in tracts implicated in emotion regulation and cognitive processing. More phenotypically mature UF WM may be adaptive against internalizing psychopathology in adolescents exposed to ELS. 相似文献