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981.
982.
Filipek PA Juranek J Nguyen MT Cummings C Gargus JJ 《Journal of autism and developmental disorders》2004,34(6):615-623
A random retrospective chart review was conducted to document serum carnitine levels on 100 children with autism. Concurrently drawn serum pyruvate, lactate, ammonia, and alanine levels were also available in many of these children. Values of free and total carnitine (p < 0.001), and pyruvate (p=0.006) were significantly reduced while ammonia and alanine levels were considerably elevated (p < 0.001) in our autistic subjects. The relative carnitine deficiency in these patients, accompanied by slight elevations in lactate and significant elevations in alanine and ammonia levels, is suggestive of mild mitochondrial dysfunction. It is hypothesized that a mitochondrial defect may be the origin of the carnitine deficiency in these autistic children. 相似文献
983.
984.
Neuroendocrine aspects of chronic fatigue syndrome 总被引:1,自引:0,他引:1
Papanicolaou DA Amsterdam JD Levine S McCann SM Moore RC Newbrand CH Allen G Nisenbaum R Pfaff DW Tsokos GC Vgontzas AN Kales A 《Neuroimmunomodulation》2004,11(2):65-74
Chronic fatigue syndrome (CFS) is a serious health concern affecting over 800000 Americans of all ages, races, socioeconomic groups and genders. The etiology and pathophysiology of CFS are unknown, yet studies have suggested an involvement of the neuroendocrine system. A symposium was organized in March 2001 to explore the possibility of an association between neuroendocrine dysfunction and CFS, with special emphasis on the interactions between neuroendocrine dysfunction and other abnormalities noted in the immune and autonomic nervous systems of individuals with CFS. This paper represents the consensus of the panel of experts who participated in this meeting. 相似文献
985.
986.
Mohajeri MH Gaugler MN Martinez J Tracy J Li H Crameri A Kuehnle K Wollmer MA Nitsch RM 《Neuro-degenerative diseases》2004,1(4-5):160-167
The accumulation of the beta-amyloid peptide (Abeta) is a central event in the pathogenesis of Alzheimer's disease (AD). Abeta removal from the brain by immune therapy shows promising potential for the treatment of patients with AD, although the mechanisms of the antibody action are incompletely understood. In this study we compared the biological activities of antibodies raised against various Abeta fragments for Abeta reduction in vitro and in vivo. Antibodies against Abeta enhanced the uptake of Abeta42 aggregates up to 6-fold by primary microglial cells in vitro. The kinetics of Abeta42 uptake varied considerably among antibodies. Based on the activity to mediate Abeta42 uptake by microglial cells, we identified a bioactive antibody that significantly reduced Abeta42 levels in the brains of transgenic mice with neuronal expression of an AD-related mutated amyloid precursor protein. This effect depended on the epitopes recognized by the antibody. Our data suggest that the ability to facilitate Abeta42 uptake by primary microglia cells in vitro can be used to predict the biological activity of the antibody by passive immunization in vivo. This protocol may prove useful for the rapid validation of the activity of antibodies designed to be used in immune therapy of AD. 相似文献
987.
The objective of this paper is to evaluate the efficacy of gepirone immediate-release (gepirone-IR) for relapse prevention in outpatients with MDD who had responded to initial gepirone-IR therapy. Patients with MDD and a HAM-D(25) score > or = 20 were treated with open-label gepirone-IR 20 to 90 mg/day for 6 weeks. Responders with a HAM-D(17) total score < or = 12 or with a > or = 50% reduction in total HAM-D(17) score and at least a "much improved" or "very much improved" CGI improvement score, were randomized to gepirone-IR or placebo for six additional weeks. Time to relapse was defined in six ways [(1) return to > or = 75% of baseline HAM-D(17) total score; (2) CGI improvement score of "no change" or "minimally worse," "much worse" or "very much worse" than baseline (> or = 4); and four more definitions combining the HAM-D(17) or CGI criteria with discontinuation, or discontinuation due to lack of efficacy] and analyzed for the ITT population using the LOCF method. Of 134 patients in the open-label phase, 70 were responders. In the double-blind phase, the relapse rate was significantly lower with gepirone-IR than with placebo (P < or = 0.05) for four of the six definitions of relapse. Discontinuations of gepirone-IR due to adverse events were observed for 26.9% of patients in the open-label phase, and four patients (6%) during the double-blind phase. The most frequent adverse events with gepirone-IR were dizziness, nausea, headache, and somnolence, and with placebo were headache and paresthesia. A relapse-prevention study of longer duration is needed to confirm these preliminary results. Gepirone-IR was significantly more effective than placebo for relapse prevention and demonstrated acceptable tolerability in outpatient responders with MDD. 相似文献
988.
Colón-Emeric CS Caminis J Suh TT Pieper CF Janning C Magaziner J Adachi J Rosario-Jansen T Mesenbrink P Horowitz ZD Lyles KW;HORIZON Recurrent Fracture Trial 《Current medical research and opinion》2004,20(6):903-910
OBJECTIVE: To present the novel design of a trial testing the safety and efficacy of a yearly bisphosponate, zoledronic acid, in preventing new clinical fractures in patients with recent low trauma hip fracture repair. Research design and methods: Randomized, placebo-controlled, triple-blind study. One hundred and fifteen clinical centers worldwide are recruiting approximately 1714 subjects aged 50 years and over (no upper age limit, median age of enrolled subjects to date 79 years) who have undergone surgical repair of a low trauma hip fracture in the preceding 90 days. Patients will be assigned at random to an intervention group (5 mg zoledronic acid intravenously yearly) or a control group (placebo infusion yearly). Both groups receive a loading dose of Vitamin D2 or D3 IM or orally, followed by 800-1200 IU Vitamin D and 1000-1500 mg elemental calcium orally on a daily basis. Concomitant therapy with calcitonin, hormone replacement therapy, selective estrogen receptor modulators, tibolone, and external hip protectors are allowed. MAIN OUTCOME MEASURES: The primary endpoint is subsequent skeletal fractures as adjudicated by a clinical endpoints committee blinded to intervention status. Secondary outcomes include delayed hip fracture healing, changes in bone mineral density, and health resource utilization. Subjects will be recruited over a 3-4 year period and will be followed until 211 primary endpoints are accrued and adjudicated. CONCLUSIONS: This randomized clinical trial is novel among osteoporosis therapies as it (1). targets hip fracture patients, a previously understudied group, and (2). uses only clinically evident fractures as the primary outcome. Ethical and practical considerations in studying this frail population are discussed. 相似文献
989.
Asbestos fibers are well known environmental carcinogen, however, the underlying mechanisms of their action have still not clearly been identified. Asbestos is capable of depleting glutathione and generating reactive oxygen species (ROS), which are important mediators of damage in biological system. Asbestos-induced mutagenecity, may be mediated by the generation. It is known that a number of scavengers and antioxidants attenuate asbestos-induced ROS release. Furthermore, it is known that garlic, contains numerous sulfur compounds and glutathione precursors which act as antioxidants and also demonstrate anticarcinogenic properties. The aim of this study was to investigate whether garlic extract has any influence on asbestos-mediated genotoxicity. As an assay system, we applied the micronucleus assay, sister chromatid exchanges, and chromosomal aberrations with human peripheral blood lymphocytes, which has already been used to analyze the genotoxicity of asbestos fibers. Our results indicate that garlic extract, when administered to the lymphocytes cell culture simultaneously with chrysotile reduced the rates of micronucleus formation, sister chromatid exchanges, and chromosomal aberrations significantly. We conclude that garlic extract may be an efficient, physiologically tolerable quencher of asbestos-mediated genotoxicity. 相似文献
990.
We investigated the cognitive consequences of a prenatal injection of the mitotic inhibitor methylazoxymethanol (MAM) into pregnant rats at embryonic day 15 (E15) or 17 (E17). The male offspring were tested when adult on a version of the radial-arm maze task that assesses spatial working memory with an extended delay, where performance is dependent, in part, on the hippocampal-prefrontal circuit. A major impairment of spatial learning was observed in E15 MAM rats. However, the E17 MAM rats did learn the rule but were impaired selectively in the 30-min delay-interposed task. Morphologically, the E15 MAM rats exhibited dramatic gross brain abnormalities, whereas the E17 MAM animals displayed aberrant cell migration in the hippocampus and a disrupted laminar pattern in the neocortex. These results suggest that late gestational MAM injection (E17) causes a cognitive impairment in a prefrontal cortex-hippocampus-dependent working memory task. This approach could provide a new developmental model of disorders associated with working memory deficits, such as schizophrenia. 相似文献