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41.
Inactivation of human synovial fluid phospholipase A2 by the marine natural product, manoalide 总被引:2,自引:0,他引:2
The marine natural product, manoalide (MLD), was investigated to determine if this drug inhibited purified human synovial fluid phospholipase A2 (HSF-PLA2). Utilizing classical Michaelis-Menten kinetics, apparent Km and Vmax values for HSF-PLA2 of 1.34 mM and 0.47 mumol [3H]palmitic acid released/min/mg protein were obtained using dipalmitoylphosphatidylcholine (DPPC) as the substrate, and 38.0 microM and 18.8 mumol [3H]arachidonic acid released/min/mg protein with Escherichia coli as a natural substrate. These kinetic parameters were utilized subsequently to evaluate the inhibitory effects of manoalide on HSF-PLA2. Inhibition of HSF-PLA2 by MLD was concentration and time dependent with IC50 values of 0.2 and 0.02 microM for DPPC and E. coli respectively. Dialysis studies and examination of DPPC or E. coli hydrolysis versus enzyme concentration indicate that MLD is an irreversible inhibitor of HSF-PLA2. Substrate specificity was also examined in the absence and presence of MLD using dipalmitoylphosphatidylethanolamine (DPPE) as a substrate. MLD inhibited the hydrolysis of DPPE (greater than 90% inhibition at 2 microM), and preliminary results indicate that DPPC was more readily hydrolyzed than DPPE under the substrate conditions of the assay. While the cellular source of secreted HSF-PLA2 is unknown, these studies indicate that MLD can inactivate secreted phospholipase A2 isolated from patients with inflammatory joint disease. 相似文献
42.
43.
Sergio J Canovas Eric Lim Fernando Hornero Jose Montero 《European journal of cardio-thoracic surgery》2003,23(4):639-641
Left ventricular free wall rupture is a dramatic complication after myocardial infarction. We present our experience with the simple, expedient technique of patch glue repair without extracorporeal circulation. Access is obtained via median sternotomy. Evacuation of blood and haematoma is undertaken and a Goretex patch exceeding the size of infarct is fashioned. The patch is applied to the epicardium using enbrucrilate surgical glue instilled with gentle pressure against the beating heart. We performed this technique on 17 patients from 1993 to 2001, with a operative (30-day) mortality of 23.5% with a post-discharge survival of 85% at 2.2 years. 相似文献
44.
A double-blinded study was conducted to compare the effects of mupirocin and tetracycline ointments in the treatment of skin infections. 111 patients were available for clinical assessment, of which 53 were treated with mupirocin and 58 treated with tetracycline. Clinically, both groups were improved, and there was no significant difference. Bacteriological assessment however revealed a better response to mupirocin. Staphylococcus aureus and Streptococcus pyogenes were the most common organisms isolated. 99% of Staphylococci were sensitive to mupirocin compared with 61% to tetracycline and 29% to penicillin G. 57% of Group A beta haemolytic Streptococci were resistant to tetracycline compared to 14% to mupirocin. Gram-negative organisms were mostly resistant to both preparations. No side effects were observed in both treatment groups. This study suggests that mupirocin is a safe and effective topical preparation for treating most of our common skin infections. 相似文献
45.
46.
A sensitive and simplified HPLC assay of fluconazol is described. The calibration curve of fluconazol in plasma ranging 0–10 μ g/ml was linear with the correlation coefficients of 0.9900. The limit of detection was 0.3 μ g/ml. The average recovery of the drug was 89.1±9.05%. After oral administration of single dose(150mg) of fluconazol in man, Cmax and Tmax were 3 μg/ml and 4hr., respectively. 相似文献
47.
Initial management of acute urethral injuries 总被引:1,自引:0,他引:1
A study was made of 30 cases of acute urethral trauma treated over a 7-year period. There were 10 anterior and 20 posterior urethral injuries, the majority of these being partial ruptures. Posterior urethral injuries were caused by road traffic accidents in 75% of cases while 80% of the anterior urethral injuries were of the "straddle" type. There was only 1 case of iatrogenic injury to the anterior urethra. During follow-up, all patients required periodic dilatations for stricture except for the single case of iatrogenic injury. An average of 5 dilatations controlled all of the strictures except for 2 that required urethroplasties. 相似文献
48.
Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases. 相似文献
49.
Yu-Sheng Chang Pao-Hsien Chu Shih-Ming Jung Kun-Eng Lim Jaw-Ji Chu Chuen Hsueh Ying-Shiung Lee 《Cardiovascular pathology》2005,14(2):104-106
Cardiac papillary fibroelastoma (CPF) is the second most common benign neoplasm of the heart. This study describes the case of an 81-year-old man who was admitted to the hospital for severe vertigo and in whom a tumor at the right ventricular outflow tract (RVOT) was identified incidentally during echocardiography. The CPF was excised smoothly following the confirmation of its position by computed tomography. The comprehensive pathologic findings of CPF were reviewed. Detailed immunohistochemical analyses of CD34 and factor VIII-related antigen were performed on the covering endocardial cells. The unique chondroid metaplasia of fibrous tissue in this CPF has never been reported. This work is the first to present an unusual CPF at the RVOT with reactive process of fibrous connective tissue. 相似文献
50.
Effects of x-ray and CT image enhancements on the robustness and accuracy of a rigid 3D/2D image registration 总被引:2,自引:0,他引:2
A rigid body three-dimensional/two-dimensional (3D/2D) registration method has been implemented using mutual information, gradient ascent, and 3D texturemap-based digitally reconstructed radiographs. Nine combinations of commonly used x-ray and computed tomography (CT) image enhancement methods, including window leveling, histogram equalization, and adaptive histogram equalization, were examined to assess their effects on accuracy and robustness of the registration method. From a set of experiments using an anthropomorphic chest phantom, we were able to draw several conclusions. First, the CT and x-ray preprocessing combination with the widest attraction range was the one that linearly stretched the histograms onto the entire display range on both CT and x-ray images. The average attraction ranges of this combination were 71.3 mm and 61.3 deg in the translation and rotation dimensions, respectively, and the average errors were 0.12 deg and 0.47 mm. Second, the combination of the CT image with tissue and bone information and the x-ray images with adaptive histogram equalization also showed subvoxel accuracy, especially the best in the translation dimensions. However, its attraction ranges were the smallest among the examined combinations (on average 36 mm and 19 deg). Last the bone-only information on the CT image did not show convergency property to the correct registration. 相似文献