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111.
Progression of corpus callosum atrophy in Alzheimer disease 总被引:7,自引:0,他引:7
Teipel SJ Bayer W Alexander GE Zebuhr Y Teichberg D Kulic L Schapiro MB Möller HJ Rapoport SI Hampel H 《Archives of neurology》2002,59(2):243-248
BACKGROUND: Atrophy of the corpus callosum in the absence of primary white matter degeneration reflects loss of intracortical projecting neocortical pyramidal neurons in Alzheimer disease (AD). OBJECTIVES: To determine individual rates of atrophy progression of the corpus callosum in patients with AD and to correlate rates of atrophy progression with clinical disease severity and subcortical disease. METHODS: Magnetic resonance imaging-derived measurements of corpus callosum size were studied longitudinally in 21 patients clinically diagnosed as having AD (mean observation time, 17.0 +/- 8.5 months) and 10 age- and sex-matched healthy controls (mean observation time, 24.1 +/- 6.8 months). RESULTS: Corpus callosum size was significantly reduced in AD patients at baseline. Annual rates of atrophy of total corpus callosum, splenium, and rostrum were significantly larger in AD patients (-7.7%, -12.1%, and -7.3%, respectively) than in controls (-0.9%, -1.5%, and 0.6%, respectively). Rates of atrophy of the corpus callosum splenium were correlated with progression of dementia severity in AD patients (rho = 0.52, P<.02). The load of subcortical lesions at baseline (P<.05) predicted rate of anterior corpus callosum atrophy in healthy controls. Rates of atrophy of corpus callosum areas were independent of white matter hyperintensity load in patients with AD. CONCLUSIONS: Measurement of corpus callosum size allows in vivo mapping of neocortical neurodegeneration in AD over a wide range of clinical dementia severities and may be used as a surrogate marker for evaluation of drug efficacy. 相似文献
112.
The apolipoprotein E4 (apoE4) genotype is a major risk factor for Alzheimer's disease (AD); however, the mechanism is unknown. We previously demonstrated that apoE isoforms differentially modulated neurite outgrowth in embryonic neurons and in neuronal cell lines. ApoE3 increased neurite outgrowth whereas apoE4 decreased outgrowth, suggesting that apoE4 may directly affect neurons in the brain. In the present study we examined the effects of apoE on neurite outgrowth from cultured adult mouse cortical neurons to examine if adult neurons respond the same way that embryonic cells do. The results from this study demonstrated that (1) cortical neurons derived from adult apoE-gene knockout (apoE KO) mice have significantly shorter neurites than neurons from adult wild-type (WT) mice; (2) incubation of cortical neurons from adult apoE KO mice with human apoE3 increased neurite outgrowth, whereas human apoE4 decreased outgrowth in a dose-dependent fashion; (3) the isoform specific effects were abolished by incubation of the neurons with either receptor associated protein (RAP) or lactoferrin, both of which block the interaction of apoE-containing lipoproteins with the low-density lipoprotein receptor-related protein (LRP). These data suggest a potential mechanism whereby apoE4 may play a role in regenerative failure and accelerate the development of AD. 相似文献
113.
Maio RF Garrison HG Spaite DW Desmond JS Gregor MA Stiell IG Cayten CG Chew JL Mackenzie EJ Miller DR O' Malley PJ 《Annals of emergency medicine》2002,40(2):172-179
The purpose of the Emergency Medical Services Outcomes Project (EMSOP) is to develop a foundation and framework for out-of-hospital outcomes research. In prior work (EMSOP I), discomfort had the highest weighted score among outcome categories for the top 3 adult conditions (ie, minor trauma, respiratory distress, chest pain) and the first and third highest rankings for children's conditions (ie, minor trauma, respiratory distress). In this fourth article in the EMSOP series, we discuss issues relevant to the measurement of pain in the out-of-hospital setting, recommended pain measures that require evaluation, and implications for outcomes research focusing on pain. For adults, adolescents, and older children, 2 verbal pain-rating scales are recommended for out-of-hospital evaluation: (1) the Adjective Response Scale, which includes the responses "none," "slight," "moderate," "severe," and "agonizing," and (2) the Numeric Response Scale, which includes responses from 0 (no pain) to 100 (worst pain imaginable). The Oucher Scale, combining a visual analog scale with pictures, seems most promising for out-of-hospital use among younger children. Future research in out-of-hospital care should be conducted to determine the utility and feasibility of these measures, as well as the effectiveness of interventions for pain relief. 相似文献
114.
Garrison HG Maio RF Spaite DW Desmond JS Gregor MA O'Malley PJ Stiell IG Cayten CG Chew JL Mackenzie EJ Miller DR 《Annals of emergency medicine》2002,40(1):79-88
The purpose of the Emergency Medical Services Outcomes Project (EMSOP) is to develop a foundation and framework for out-of-hospital outcomes research. Fundamental to that purpose is the identification of priority conditions, risk-adjustment measures (RAMs), and outcome measures. In this third EMSOP article, we examine the topic of risk adjustment, discuss the relevance of risk adjustment for out-of-hospital outcomes research, and recommend RAMs that should be evaluated for potential use in emergency medical services (EMS) research. Risk adjustment allows better judgment about the effectiveness and quality of alternative therapies; it fosters a better comparison of potentially dissimilar groups of patients. By measuring RAMs, researchers account for an important source of variation in their studies. Core RAMs are those measures that might be necessary for out-of-hospital outcomes research involving any EMS condition. Potential core RAMs that should be evaluated for their feasibility, validity, and utility in out-of-hospital research include patient age and sex, race and ethnicity, vital signs, level of responsiveness, Glasgow Coma Scale, standardized time intervals, and EMS provider impression of the presenting condition. Potential core RAMs that could be obtained through linkage to other data sources and that should be evaluated for their feasibility, validity, and utility include principal diagnosis and patient comorbidity. We recommend that these potential core RAMs be systematically evaluated for use in risk adjustment of out-of-hospital patient groups that might be used for outcomes research 相似文献
115.
116.
Julie R. Houghton Ellen van Kleef Gene Rowe Lynn J. Frewer 《Health, risk & society》2006,8(2):165-183
Consumer perceptions of food hazards and how the associated risks are managed are likely to be an important determinant of consumer confidence in food safety. While there is a body of research that examines public perceptions of various types of food hazards, less attention has been directed to understanding how the public perceives food risk management practices. Utilizing elements of the repertory grid approach in focus group discussions, this research explored public attitudes regarding the effectiveness of current food risk management practices in four European countries (Denmark, Germany, Greece and the UK). While the issue of food safety did not emerge as a key factor in everyday food choice, participants were concerned about health aspects of food. There were three main factors that participants considered to be evidence of ‘good’ food risk management: the existence of identifiable control systems that respond quickly to contain a risk, the instigation of preventive measures and the availability of information that offers individuals the ability to exercise informed choice. These evaluations were similar in each of the countries under consideration and were linked to ideas regarding the controllability of risks and to questions of who is responsible for managing the risks. 相似文献
117.
E Laporte-Turpin M O Marcoux G Machado Y Dulac I Claudet E Grouteau C Puget 《Archives de pédiatrie》2005,12(7):1112-1115
Vascular Ehlers-Danlos syndrome(EDS) is at high risk of death by arterial rupture. CASE REPORT: A 13-year-old boy with vascular EDS and aortic dissection was admitted in pediatric emergency care unit. The children died after surgery by massive hemorrhage and prosthetic rupture. DISCUSSION: The precocity of this vascular accident EDS is uncommon. It occurred despite clinical and echocardiographic follow-up. The death of the children confirmed the difficulties in surgery of vascular manifestation, even if appropriate and rapid management was already done. CONCLUSION: Patients with vascular EDS must be identified because of its lethal complications. Friability of the vessels makes surgical treatment difficult. A trial using beta blockers therapy is ongoing. 相似文献
118.
Persistent serpentine supravenous hyperpigmented eruption as an adverse reaction to chemotherapy combining actinomycin and vincristine 总被引:1,自引:0,他引:1
A 15-year-old boy experienced a macular serpentine erythematous eruption that subsided with a persistent hyperpigmentation overlying the superficial venous network of the left forearm. This reaction occurred at the injection site of a chemotherapy regimen that combined actinomycin and vincristine a few hours after the first course. After a single injection of actinomycin in the right arm, a similar reaction occurred, implicating it as the responsible agent. A skin biopsy specimen demonstrated a cell-poor interface tissue reaction associated with an eccrine neutrophilic hidradenitis. To our knowledge, this is the first case of persistent supravenous serpentine hyperpigmented eruption reported in a child treated with this particular drug combination. 相似文献
119.
Wen SW Demissie K Liu S Marcoux S Kramer MS 《Paediatric and perinatal epidemiology》2000,14(4):300-304
This study examined the relationship between male sex at birth and placenta praevia in 433031 mother/infant dyads (linked by a common institutional code and hospital admission number) in the Canadian province of Quebec, during the fiscal years of 1991/92-1995/96. The male-to-female ratio among pregnancies with and without placenta praevia was calculated and compared. The male-to-female ratio at birth was higher in pregnancies complicated by a placenta praevia (1.19) than in those without it (1.04; P < 0.02). This increased ratio persisted after accounting separately for the potential confounding and/or modifying effects of maternal age, infant birthweight and gestational age by stratified and multiple logistic regression analyses. We conclude that pregnant women with male babies carry a higher risk of placenta praevia. 相似文献
120.