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Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function.  相似文献   
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Conclusion  The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list, suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high risk.”. An objective review of existing indications focused on only those indications that had significant variability among the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends that the grades for 6 indications be re-evaluated. The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards. Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee. Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20.  相似文献   
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Dapsone, used for prevention of Pneumocystis jirovecii infections, has been reported to cause hemolytic anemia and methemoglobinemia; its tolerability in solid organ transplant recipients is not well described. We investigated dapsone-related adverse events in patients undergoing solid organ transplantation from 1999 to 2004. Transplant providers identified patients for the investigators who then reviewed the patients' hospital and outpatient records. Sixteen solid organ transplant recipients fit case definitions for dapsone-related hemolytic anemia (n = 11) or methemoglobinemia (n = 5). Median time from event to dapsone discontinuation was 15 days; all patients improved after drug discontinuation. G6PD enzyme activity was normal in all patients whose test results were available. Dapsone may be associated with hemolytic anemia or methemoglobinemia, even with normal G6PD levels. These events are often not promptly recognized, and drug discontinuation is delayed. Dapsone-related hemolytic anemia or methemoglobinemia should be considered in solid organ transplant recipients with unexplained anemia or hypoxia.  相似文献   
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OBJECTIVES: Brain edema occurs following clinical as well as experimental cardiac arrest (CA) and predicts a poor neurologic outcome. The objective of this study was to determine the expression of cerebral cortex aquaporin (AQP)-4, a member of a family of membrane water-channel proteins, in brain edema formation following normothermic or hypothermic CA. METHODS: Twenty-four rats were subjected to time-matched normothermic (N-Sham, 37.5 degrees C +/- 0.5 degrees C, n = 6) or hypothermic (H-Sham, 34 degrees C +/- 0.5 degrees C, n = 6) sham experiments and normothermic (N-CA, n = 6) or hypothermic (H-CA, n = 6) CA induced by asphyxiation for 8 minutes. Hypothermia was induced before CA. The animals were resuscitated with cardiopulmonary resuscitation, ventilation, and epinephrine administration. Brain edema was determined by brain wet-to-dry weight ratio at one hour of resuscitation. AQP4 immunoactivity in the cerebral cortex was determined using immunohistochemical staining and was semiquantified as an intensity of staining with an automated cell imaging system. RESULTS: Mild hypothermia in the sham experiments did not alter cerebral cortex AQP4 immunoactivity (mean +/- SD) (55.0 +/- 3.7 in H-Sham vs. 53.3 +/- 1.7 in N-Sham, p > 0.05). N-CA resulted in a significant increase in AQP4 immunoactivity (61.8 +/- 4.5) compared with N-Sham (p = 0.01) and H-Sham (p = 0.03). H-CA attenuated AQP4 compared with N-CA (53.4 +/- 1.3, p = 0.01). Brain wet-to-dry weight ratios were 4.41 +/- 0.07 in N-Sham, 4.40 +/- 0.08 in H-Sham (p > 0.05 vs. N-Sham), 4.55 +/- 0.04 in N-CA (p = 0.004 vs. N-Sham; p = 0.005 vs. H-Sham), and 4.43 +/- 0.09 in H-CA (p = 0.02 vs. N-CA; p > 0.05 vs. N-Sham and H-Sham). CONCLUSIONS: Cerebral cortical AQP4 expression is up-regulated after normothermic CA, which is attenuated by hypothermia induced before CA.  相似文献   
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