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BACKGROUND: Inflammatory and/or immune activation occurs both in animal models (twitcher mice) and in the brain of patients with Globoid cell leukodystrophy (GLD) or Krabbe's disease (KD). In this study we evaluated in vitro the cytokine profile of KD patients and the effect of psychosine, the toxic metabolite which plays a role in the demyelination process in these patients. MATERIALS AND METHODS: We studied cytokine production by peripheral blood mononuclear cells (PBMCs) isolated from four KD patients, diagnosed on the basis of clinical criteria. Cells were cultured and stimulated with appropriate agents and the supernatants collected before and after the addition of psychosine. Tumour necrosis factor-alpha (TNF-alpha), interleukin-8 (IL-8) and monocyte chemoattractant factor (MCP)-1) production was evaluated (ELISA method) and compared with a group of 10 normal subjects. RESULTS: We found a significant increase of TNF-alpha release by PBMCs of KD patients compared with healthy subjects; TNF-alpha production was significantly increased after LPS addition. Psychosine was able to induce a further significant increase (P < 0.05) only in cells obtained from KD patients and not from control subjects. No changes were found in IL-8 and MCP-1 production. CONCLUSIONS: The increased TNF-alpha production permits us to confirm the presence of an inflammatory-immune stimulus in KD patients, which may be induced and potentiated by the pathogenetic metabolite psychosine.  相似文献   
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IntroductionNew radiological tools can accurately provide preoperative three-dimensional spatial assessment of metastatic renal cell carcinoma (RCC). We aimed to determine whether the distribution, volume, shape, and fraction of RCC resected in a cytoreductive nephrectomy associates with survival.MethodsWe retrospectively reviewed 560 patients undergoing cytoreductive nephrectomy, performing a comprehensive volumetric analysis in eligible patients of all detectable primary and metastatic RCC prior to surgery. We used Cox regression analysis to determine the association between the volume, shape, fraction resected, and distribution of RCC and overall survival (OS).ResultsThere were 62 patients eligible for volumetric analysis, with similar baseline characteristics to the entire cohort, and median survivor followup was 34 months. Larger primary tumors were less spherical, but not associated with different metastatic patterns. Increased primary tumor volume and tumor size, but not the fraction of tumor resected, were associated with inferior survival. The rank of tumors based on unidimensional size did not completely correspond to the rank by primary tumor volume, however, both measurements yielded similar concordance for predicted OS. Larger tumor volume was not associated with a longer postoperative time off treatment.ConclusionsPrimary tumor volume was significant for predicting OS, while the fraction of disease resected did not appear to impact patient outcomes. Although rich in detail, our study is potentially limited by selection bias. Future temporal studies may help elucidate whether the primary tumor shape is associated with tumor growth kinetics.  相似文献   
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A medicated plaster containing diclofenac epolamine (DHEP) and heparin has been recently proposed for the treatment of local trauma (ie, ankle sprains) accompanied by a clinically significant edema and/or hematoma formation, based on the combined antiinflammatory, hemorheologic, and antiedema properties of diclofenac and heparin. The aim of this study was therefore to compare the effects of a combined DHEP/heparin and DHEP alone in 2 clinical experimental models of microangiopathy, in order to provide a pharmacologic rationale for association of diclofenac and heparin. The microcirculation was evaluated by measuring cutaneous blood flow (laser Doppler) and transcutaneous oxygen and carbon dioxide pressures (TcPO(2) and TcPCO(2)) in 10 healthy volunteers before and after producing 2 microcirculatory models of microangiopathy: the models were based on reactive hyperemia (RH) and on local histamine injection, which both produce a significant increase in skin flux and alterations of TcPO(2) and TcPCO(2). The area of the study was the distal medial leg, treated with placebo, DHEP alone (Flector Tissugel), and DHEP/heparin (Flector Tissugel Heparin). The plasters were applied before producing the microcirculatory models to evaluate the efficacy of DHEP and DHEP/heparin in controlling and limiting vasodilatation and development of microangiopathy. A significant increase in cutaneous flux was obtained with both models. The application of DHEP partially limited the increase in flux and in TcPCO(2), as well as the decrease in TcPO(2) (which were considered signs of microangiopathy), but the combination DHEP/heparin was significantly more effective than DHEP alone. The inclusion of heparin in the plaster thus improved the control of the microcirculation achieved with diclofenac alone, when an experimental model of venous/arterial hyperemia and microangiopathy was used. In conclusion, DHEP in association with heparin modulates microcirculatory changes better than DHEP alone. It should be interesting to investigate the product in comparable clinical conditions in which it may be useful to act pharmacologically both on inflammation and microcirculatory disturbances that delay the recovery of patients.  相似文献   
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Research in genetics of epilepsy represents an area of great interest both for clinical purposes and for understanding the basic mechanisms of epilepsy. Most mutations in epilepsies without structural brain abnormalities have been identified in ion channel genes, but an increasing number of genes involved in a diversity of functional and developmental processes are being recognized through whole exome or genome sequencing. Targeted molecular diagnosis is now available for different forms of epilepsy. The identification of epileptogenic mutations in patients before epilepsy onset and the possibility of developing therapeutic strategies tested in experimental models may facilitate experimental approaches that prevent epilepsy or decrease its severity. Functional analysis is essential for better understanding pathogenic mechanisms and gene interactions. In vitro experimental systems are either cells that usually do not express the protein of interest or neurons in primary cultures. In vivo/ex vivo systems are organisms or preparations obtained from them (e.g., brain slices), which should better model the complexity of brain circuits and actual pathophysiological conditions. Neurons differentiated from induced pluripotent stem cells generated from the skin fibroblasts of patients have recently allowed the study of mutations in human neurons having the genetic background of a given patient. However, there is remarkable complexity underlying epileptogenesis in the clinical dimension, as reflected by the fact that experimental models have not provided yet results having clinical translation and that, with a few exceptions concerning rare conditions, no new curative treatment has emerged from any genetic finding in epilepsy.  相似文献   
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We describe a patient with a subarachnoid hemorrhage that presented with electrocardiographic evidence of transmural myocardial infarction. The patient was found to have normal coronaries and on autopsy revealed generalized myocytolysis with no evidence of transmural myocardial infarction. This case illustrates the value of acute coronary angiography in patients with altered mental status and suspected myocardial infarction. © 1996 Wiley-Liss, Inc.  相似文献   
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We investigated the effect of Lewis Lung carcinoma cells on the production of C3 by murine macrophages and examined the capacity of secreted C3 to opsonize Lewis Lung carcinoma cells. C3 released in culture from macrophages obtained from tumor-bearing C57Bl/6 mice as well as from normal macrophages exposed to Lewis Lung carcinoma cells in vitro was measured by hemolytic assays and by Western blot. We found that contact with tumor cells in vivo as well as in vitro enhanced the amount of C3 secreted by murine macrophages by a factor of 2-3. The inflammatory agent carrageenan caused only a small increase in the amount of secreted C3. On Western blots of concentrated macrophage supernatants, there was partial cleavage of secreted C3 which was, however, not more pronounced in the case of C3 from tumor-stimulated macrophages than from normal macrophages. Supernatants from normal as well as tumor-stimulated macrophages were capable of opsonizing Lewis Lung carcinoma cells as shown by their capacity to bind human erythrocyte in an immune adherence reaction. Pretreatment of the tumor cells with a protease inhibitor, PMSF, inhibited the capacity of the tumor cells to bind C3, suggesting that a tumor cell-associated protease might be involved in the binding of C3 to the tumor cell surface.  相似文献   
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