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1.
We report the development of a serodiagnostic method for Mycobacterium avium complex (MAC) disease with an enzyme immunoassay (EIA) with the MAC-specific glycopeptidolipid (GPL) core as the antigen. In this study, we confirmed by EIA that the GPL core antibody was in the sera of immunocompetent patients with MAC disease. The EIA for quantifying the GPL core antibody was evaluated as a clinical tool for serodiagnosis of pulmonary MAC disease. A significant increase in GPL core antibodies (immunoglobulins G, A, and M) was detected in sera of patients with MAC pulmonary diseases when they were compared to patients who were colonized with MAC, patients with Mycobacterium kansasii disease or tuberculosis, and healthy subjects. The sensitivities and specificities of the GPL core-based EIA for diagnosis of MAC pulmonary disease were 72.6% and 92.2%, respectively, for IgG, 92.5% and 95.1%, respectively, for IgA, and 78.3% and 91.0%, respectively, for IgM. The best sensitivity and specificity were obtained by measuring immunoglobulin A antibodies against GPL core antigen. The level of GPL core antibodies reflected disease activity, since it decreased in cured MAC patients who had responded to chemotherapy. Measurement of serum antibodies against GPL core is useful for both diagnosis and assessment of disease activity in MAC disease of the lung.  相似文献   
2.
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.  相似文献   
3.
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506, have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients). CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7 pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury of the liver graft, possibly by modulating effects of TNF-α.  相似文献   
4.
Background and Aims: Chemokines and their receptors have recently been shown to have major roles in cancer metastasis. The aim of this study was to determine whether the interaction between chemokine receptor 6 (CCR6) and its ligand, macrophage inflammatory protein‐3 alpha (MIP‐3α), correlates with metastasis of hepatocellular carcinoma (HCC). Methods: To observe the reaction of CCR6 expressed cancer cells to MIP‐3α stimulation, chemotactic and actin polymerization assays for both CCR6 high cells (HepG2) and CCR6 low cells (MCF‐7) were performed. CCR6 mRNA levels in tumor specimens from 30 HCC patients were quantified by real‐time polymerase chain reaction. Patients were classified into two groups, high (≥ 20 copies; n = 10) CCR6 and low (<20 copies; n = 20) CCR6 on the basis of CCR6 expression, and the groups were compared with respect to clinicopathological features. Results: When HepG2 cells (CCR6 high) were stimulated with MIP‐3α, they migrated in a dose‐dependent manner, and formation of pseudopodia was observed. These phenomena were not observed in the CCR6 low cells. The incidence of intrahepatic metastasis was higher in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Disease‐free survival was significantly poorer in the high CCR6 expression group than in the low CCR6 expression group (P < 0.05). Conclusions: It was indicated that CCR6 might be associated with intrahepatic metastasis of HCC and might be able to become one of the prognostic factor after hepatic resection for HCC.  相似文献   
5.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
6.
PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation.  相似文献   
7.
Thallium-201 SPECT was performed to evaluate a pulmonary lesion in a 73-year-old male which had been considered to be an inflammatory lesion for two years. The lesion has slowly increased in size on x-CT. Tl-201 was intensely taken up and retained in the lesion, suggesting a malignant lesion. Histological examination revealed that the lesion was bronchioloalveolar carcinoma. This case suggested that Tl-201 uptake of pulmonary carcinoma would not be necessarily related to cell growth rate.  相似文献   
8.
The diastereoisomeric glucuronic acid conjugates of R/S-benoxaprofen are the major benoxaprofen metabolites and are found in urine at high concentrations. The conjugates of R- and S-benoxaprofen can be separated directly on a C18 reversed-phase column using a mixture of acetonitrile and tetrabutylammonium hydroxide buffer, pH 2.5 (28:72, v/v), as the mobile phase. The k values of S- and R-benoxaprofen glucuronides are 57.5 and 63.0, respectively. Diluted urine or deproteinized plasma samples were injected without further treatment. With fluorescence detection at 313/365 nm, quantifiable limits of 50 ng equiv./ml were found for the conjugates. The intra- and interday variability was below 12%. Utilizing this analytical procedure it is possible to characterize enantioselective glucuronidation both in vivo and in vitro. For in vitro procedures, apparent rates of formation and the R/S ratio may be substrate (benoxaprofen) and cosubstrate (UDPGA) dependent. Moreover, enantioselective cleavage of the formed benoxaprofen glucuronides by alkaline hydrolysis, hydrolytic enzymes, and acyl migration must be controlled for both in vitro and in vivo studies since R-benoxaprofen glucuronide is degraded faster than the S-diastereomer under certain conditions.  相似文献   
9.
10.
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis.  相似文献   
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