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There is a well-recognized association between dysontogenetic tumors of the spinal cord (including teratomas and enterogenous cysts) and dysraphic congenital spinal malformations. The authors present a case of an adult with an intramedullary mature teratoma (IMMT) at the level of C1-2 of the cord associated with dysraphic congenital spinal malformations. Intramedullary mature teratomas of the cervical region of the spinal cord are very rare in adults; only four such lesions have been reported, two of which involved upper cervical segments. Despite the potentially critical location of the tumor, monitored microsurgery resulted in complete removal of the tumor with an intact surrounding capsule, associated fibrous tract, and ellipse of skin with a central dimple. There was an excellent postoperative neurological outcome. The clinical features, imaging studies, treatment options, postoperative outcome, and plausible pathological correlations of IMMTs are discussed.  相似文献   
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ObjectiveThis is a prospective study of patients with LVEF ≤40%, with the objective of correlating CV events to LGE detected and quantified by CMRI.MethodsHeart Failure (HF) patients with LVEF <40% who underwent CMRI were included. LGE volume of ≥6% of the myocardial volume was considered significant. Data of appropriate ICD shocks, CV hospitalizations and mortality were recorded.ResultsThere were 133 HF (72 ICM & 62 NIDCM) patients with a mean age of 54 ± 12 years, mean LVEF of 34 ± 6% and a follow up of 24 ± 3 months. Totally 46 CV events were recorded in 30 patients, 44 in LGE +ve & 2 in LGE -ve groups (HR 17.8, 95% CI-8.03-39.3, P = 0.000095). All the 7 deaths were in LGE +ve group. CV events were 22 (30.5%) in ICM group and 8 (13.1%) in NIDCM group (p = 0.03). All the 22 ICM patients and 6 of the 8 NIDCM with CV events were LGE +ve. The distribution of CV events amongst LGE +ve and LGE -ve were 35 vs 0 (ICM) and 9 vs 2 (NIDCM); p < 0.005.CV events in LVEF ≤ 30% group, were seen in 19 (47.5%) vs 1 (5.8%) in LGE +ve vs LGE -ve and no of events were 29 vs 1 (p = 0.003). In those with LVEF >30% the corresponding figures were 9 (22.5%) vs 1 (2.8%) and 15 vs 1 respectively (p = 0.02).ConclusionDemonstration of significant LGE by CMRI indicates high risk occurrence of CV events (CV hospitalization, appropriate shocks and total mortality) in NIDCM & ICM patients with LVEF < 40%.  相似文献   
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Characterization of folate-chitosan-DNA nanoparticles for gene therapy   总被引:19,自引:0,他引:19  
Gene therapy using polymers such as chitosan shows good biocompatibility, but low transfection efficiency. The mechanism of folic acid (FA) uptake by cells to promote targeting and internalization could improve transfection rates. The objective of this study was to synthesize and characterize FA-chitosan-DNA nanoparticles and evaluate their cytotoxicity in vitro. Chitosan-DNA and FA-Chitosan-DNA nanoparticles were prepared using reductive amidation and a complex coacervation process. The effect of charge ratio on the properties of these nanoparticles was monitored by laser scattering. DNA inclusion and integrity was evaluated by gel electrophoresis. Cell viability was illustrated with the MTT assay. Charge ratio (N/P) controlled the nanoparticles size and their zeta potential. Nanoparticles presented a mean size of 118 nm and 80% cellular viability compared to 30% cell viability using LipofectAMINE2000 controls. Gel electrophoresis showed intact DNA within the carriers. FA-nanoparticles have lower cytoxicity, good DNA condensation, positive zeta potential and particle size around 118 nm, which makes them a promising candidate as a non-viral gene vector.  相似文献   
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Cathepsin D protein patterns were analyzed in 59 colorectal tumors by Western blotting, glycosylation and immunohistochemical assays. Measurement of protein content by laser densitometry of tumor/normal pairs on Western blots revealed loss of cathepsin D protein in more than 50% of colorectal tumors. Independent loading controls and statistical estimates of reproducibility on duplicate assays confirmed frequent decreases in cathepsin D. For cases having a tumor/normal ratio (T/N) <1, the average T/N was 0.50+/-0.19, equivalent to the loss of one cathepsin D allele. However, 2-fold increases in cathepsin D protein levels were also observed in approximately 1/3 of tumors, supporting the concept that colorectal cancers develop via divergent molecular pathways and that cathepsin D may function differently in different cancers. Although normal cathepsin D expression was detected in some earlier stage tumors, protein levels became increasingly bimodal with progression such that cathepsin D levels were increased in 1/3 but decreased in 2/3 of stage III and IV cancers. Other laboratories have reported both significant loss and gain of chromosome 11 (site of the cathepsin D gene) in different colorectal tumors, providing a possible mechanism for our observations on cathepsin D. However, differential regulation of cathepsin D expression by mutant versus wild-type p53 may also contribute to variable cathepsin D levels in colorectal cancers. Immunohistochemical studies demonstrated a shift from a predominantly punctate distribution of cathepsin D protein in normal mucosa to a more diffuse cytoplasmic distribution in tumor tissues. Mutant forms of cathepsin D were not detected in tumors either as changes in electrophoretic mobility or altered glycosylation but minor changes in protein sequence could not be ruled out. Loss of cathepsin D protein may provide an advantage to colorectal tumors related to a loss of cathepsin D function in proapototic or antiangiogenic pathways while increased cathepsin D may promote cancer cell proliferation or invasion.  相似文献   
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Primary cytomegalovirus (CMV) infection is common in infancy with approximately 90% to 95% of subjects developing antibodies against this virus. CMV seronegative renal allograft recipients generally receive this infection with a graft or with blood transfusions, showing a high morbidity and mortality. Prophylaxis in these patients has shown good results; however, the published studies have included a small number of patients. Our case-controlled study evaluated 163 kidney transplant recipients: 76 seronegatives for CMV and 87 seropositive for CMV as controls. The evaluated parameters were: CMV infection, CMV disease, renal function, and survival of the patient and graft. We studied our experience among CMV seronegative patients treated with various prophylaxis guidelines. Our conclusions were that CMV prophylaxis in seronegative patients was effective because it showed a risk of infection that was equal (or even less) than that in seropositive patients and revealed a delay in the onset of the disease. CMV seronegativity may be a positive prognostic factor for graft survival.  相似文献   
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