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41.
There are accumulating studies that report a neurogenic potential of bone marrow-derived cells both in vitro as well as in vivo. Most claims of neural "transdifferentiation" have based their conclusions on morphology and neural gene expression. Recently, doubts have been raised about the validity of both outcome parameters since non-neural cells can extend neurites and show aberrant neural gene expression as a response to stress inducing factors. In this study, we compared bone marrow-derived Multipotent Adult Progenitor Cell (MAPC)-like cells and neural stem cells (NSC) in their morphology and neural gene expression profile after neural differentiation using three differentiation protocols. We evaluated the expression of five neuroglial antigens [neurofilament 200 (NF200); beta III tubulin (beta3 tub); tau; Glial Fibrillary Acidic Protein (GFAP); Myelin Basic Protein (MBP) and RIP antigen] using real-time PCR (RT-PCR) and immunocytochemistry (ICC). MAPC-like cells adopted a neural-like morphology in one protocol but a fibroblast-like morphology in the two other protocols. RT-PCR and ICC show that MAPC-like cells already express the neural antigens beta III tubulin and NF200 at baseline, but no upregulation of these genes after exposure to three distinct differentiation protocols was seen. In contrast, NSC adopt neural and glial morphologies with a clear increase in expression of all neuroglial genes in all differentiation protocols used. In conclusion, our data demonstrate that neural-like morphology and expression of a limited set of neural marker genes by MAPC-like cells after differentiation are not absolute proof of neural transdifferentiation because MAPC-like cells only partially meet the criteria which are fulfilled by NSC after neural differentiation.  相似文献   
42.
The objective of this article was to review and summarize the available reports on the profile of the novel anticonvulsant drug levetiracetam (LEV) in a clinical setting. Therefore, a careful search was conducted in the MEDLINE database and combined with guidelines from regulatory agencies, proceedings of professional scientific meetings, and information provided by the manufacturers. This article is devoted to the clinical pharmacology and clinical trials of LEV investigating its efficacy and safety as add-on therapy or monotherapy for various seizure types. Finally, results from postmarketing surveillance of LEV are briefly discussed. In general, LEV is shown to be a safe, broad-spectrum anticonvulsant drug with highly beneficial pharmacokinetic properties, a favorable long-term retention rate, and a high responder rate, indicating that LEV is an efficient therapeutic option for the treatment of several types of epilepsy.  相似文献   
43.
The objective of this article was to review and summarize the available reports on the preclinical profile of the novel anticonvulsant drug levetiracetam (LEV). Therefore, a careful search was conducted in the MEDLINE database and combined with guidelines from regulatory agencies, proceedings of professional scientific meetings, and information provided by the manufacturers. This article provides detailed information on the anticonvulsant effects of LEV in various animal models of epilepsy and on its pharmacology in laboratory animals. The mechanism of action of LEV is reviewed, with special regard to its recently discovered binding site, the synaptic vesicle protein 2A. In general, LEV is shown to be a safe, broad-spectrum anticonvulsant drug with highly beneficial pharmacokinetic properties and a distinct mechanism of action. The clinical studies with LEV will be discussed in the second part of this review article to be published subsequently.  相似文献   
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Neurofibromatosis type I (NF1) is an autosomal dominant familial tumor syndrome characterized by the presence of multiple benign neurofibromas. In 95% of NF1 individuals, a mutation is found in the NF1 gene, and in 5% of the patients, the germline mutation consists of a microdeletion that includes the NF1 gene and several flanking genes. We studied the frequency of loss of heterozygosity (LOH) in the NF1 region as a mechanism of somatic NF1 inactivation in neurofibromas from NF1 patients with and without a microdeletion. There was a statistically significant difference between these two patient groups in the proportion of neurofibromas with LOH. None of the 40 neurofibromas from six different NF1 microdeletion patients showed LOH, whereas LOH was observed in 6/28 neurofibromas from five patients with an intragenic NF1 mutation (P = 0.0034, Fisher's exact). LOH of the NF1 microdeletion region in NF1 microdeletion patients would de facto lead to a nullizygous state of the genes located in the deletion region and might be lethal. The mechanisms leading to LOH were further analyzed in six neurofibromas. In two out of six neurofibromas, a chromosomal microdeletion was found; in three, a mitotic recombination was responsible for the observed LOH; and in one, a chromosome loss with reduplication was present. These data show an important difference in the mechanisms of second hit formation in the 2 NF1 patient groups. We conclude that NF1 is a familial tumor syndrome in which the type of germline mutation influences the type of second hit in the tumors.  相似文献   
46.
This study evaluated whether reaction times (RT) and performance variability are potential markers for the early detection of Alzheimer's disease (AD). Cognitively healthy elderly (n = 218), persons with amnestic MCI (a-MCI) (n = 29) and patients with AD (n = 50) were examined with RT tasks with increasing complexity, subdividing RT into a decision and a movement component. Persons with cognitive deterioration demonstrated more intra-individual variability and more slowing than cognitively healthy elderly. The slowing in AD affects both the cognitive and the motor component, while performance variability mainly affects the cognitive component of the RT. Although in a-MCI not all differences reached statistical significance, primarily the cognitive component of the RT is affected in a-MCI. Intra-individual variability and RT of the complex tasks are the best predictors for a-MCI and AD status, respectively. We conclude that performance variability can be regarded as a useful preclinical marker for AD.  相似文献   
47.
OBJECTIVES: At Ghent University Hospital, the feasibility and efficacy of the modified Atkins' diet was evaluated in adult patients with refractory epilepsy. The Atkins' diet restricts carbohydrate intake and was originally designed for weight loss. PATIENTS AND METHODS: During a 6-month trial period, a carbohydrate restriction of 20g/day was in place. During a 36h hospital admission, patients were instructed about the diet. Patients underwent clinical neurological testing, EEG, ECG, blood and urine analyses and mood evaluation before and during the trial. Seizure frequency and side effects were recorded in seizure diaries and followed up at monthly clinic visits. RESULTS: Eight patients were included in the study. Three out of eight patients followed the diet for 6 months. One out of three patients showed a >50% seizure reduction, 1/3>30%, and 1/3<30%. Side effects such as constipation and diarrhoea were mild and occurred mainly during the initial week of the diet. Patients reported improved concentration and well being. This was confirmed by improved scores on the Beck Depression Inventory Scale. CONCLUSION: This pilot study shows that the modified Atkins' diet is feasible in an adult population, and that seizure frequency reduction is possible. The results need to be confirmed in larger prospective, controlled studies with comparison groups.  相似文献   
48.
Muscle contracture and joint stiffness are a major concern during limb lengthening using the Ilizarov method. The aim of this study was to detect factors that may influence the final loss of knee flexion. We retrospectively studied knee movement in 32 patients undergoing femoral lengthening using the Ilizarov method. The pattern of loss of knee movement showed a rapid fall in knee flexion during the latency period between operation and start of distraction, and the flexion loss continued during lengthening. There was a relationship between the worst knee range of motion achieved during lengthening and the final loss of knee flexion. Intensive physical therapy is necessary in the latency period, because there is a rapid decrease in knee flexion, as well as during the whole lengthening procedure, in which flexion loss continues. Despite the flexion loss, patients finally regain good knee function after removal of the external fixator.  相似文献   
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Over the past decades, it has become clear that the most efficient way to prevent status epilepticus is to stop the seizure as fast as possible, and early treatment of prolonged convulsive seizures has become an integral part of the overall treatment strategy in epilepsy. Benzodiazepines are the first choice drugs to be used as emergency medication. This treatment in the early phases of a seizure often implies a ‘pre-medical’ setting before intervention of medically trained persons. In this paper, we propose “good practice points” for first line management of prolonged convulsive seizures in children and adults in a ‘pre-medical’ setting.  相似文献   
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