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991.
PURPOSE: In the present study, we investigated the association between tumor tissue levels of tissue inhibitor of metalloproteinase-1 (TIMP-1) and prognosis in patients with primary breast cancer and analyzed whether TIMP-1 may be useful as a prognostic marker in combination with urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1). EXPERIMENTAL DESIGN: In cytosolic extracts of 2984 primary breast tumors, total levels of TIMP-1 were determined using an established, validated ELISA. Levels of uPA and PAI-1 have previously been determined in the extracts. RESULTS: Univariate survival analysis showed a significant relationship between higher levels of TIMP-1 (continuous log-transformed variable) and poor prognosis [recurrence-free survival (RFS), overall survival (OS); P < 0.001]. Performing isotonic regression analysis, we identified a cut point to classify tumors as TIMP-1-low or TIMP-1-high. Using this cut point, high levels of TIMP-1 were significantly associated with shorter survival in univariate analysis, both in the total patient group (RFS, OS; P < 0.001), in the node-negative subgroup (RFS, hazard ratio = 1.28, P = 0.006), and in the node-positive subgroup (RFS, hazard ratio = 1.43, P < 0.001). In multivariate analysis, including uPA and PAI-1, TIMP-1 was significantly associated with shorter RFS, both when included as a continuous log-transformed (P = 0.03) and as a dichotomized variable (P = 0.002). CONCLUSIONS: This study validates previous findings that tumor tissue levels of TIMP-1 are associated with prognosis in patients with primary breast cancer. It confirms that TIMP-1 may be useful as a prognostic marker in combination with uPA/PAI-1 and adds substantial positive information on the use of TIMP-1 as a prognostic marker in breast cancer.  相似文献   
992.
PURPOSE: To evaluate whether lower literacy is associated with poorer knowledge and more negative attitudes and beliefs toward colorectal cancer screening among veterans without recent colorectal cancer screening. PATIENTS AND METHODS: Three hundred seventy-seven male veterans, age 50 years and older, who had not undergone recent colorectal cancer screening, were surveyed about their knowledge, attitudes, and beliefs regarding colorectal cancer screening. Patients' literacy was assessed with the Rapid Estimate of Adult Literacy in Medicine, an individually administered screening test for reading. RESULTS: Thirty-six percent of the 377 men had an eighth grade literacy level or higher. Men with lower literacy were 3.5 times as likely not to have heard about colorectal cancer (8.8% v 2.5%; P =.006), 1.5 times as likely not to know about screening tests (58.4% v 40.9%; P =.0001), and were more likely to have negative attitudes about fecal occult blood testing (FOBT), but not about flexible sigmoidoscopy. Specifically, men with lower literacy skills were two times as likely to be worried that FOBT was messy (26.7% v 13.3%; P =.008), 1.5 times as likely to feel that FOBT was inconvenient (28.7% v 18%; P =.05), and four times as likely to state they would not use an FOBT kit even if their physician recommended it (17.9% v 4.0%; P =.02). CONCLUSION: Limited literacy may be an overlooked barrier in colorectal cancer screening among veterans.  相似文献   
993.
The BIOMED-2 Concerted Action BMH4-CT98-3936 on 'Polymerase chain reaction (PCR)-based clonality studies for early diagnosis of lymphoproliferative disorders' developed standardized PCR protocols for detection of immunoglobulin (Ig) and T-cell receptor (TCR) rearrangements, including TCR beta (TCRB). As no comparable TCRB PCR method pre-existed and only a limited number of samples was tested within the BIOMED-2 study, we initiated this study for further validation of the newly developed TCRB PCR approach by comparing PCR data with previously generated Southern blot (SB) data in a series of 66 immature (ALL) and 36 mature T-cell malignancies. In 91% of cases, concordant PCR and SB results were found. Discrepancies consisted of either failure to detect SB-detected TCRB rearrangements by PCR (6.5%) or detection of an additional non-SB defined rearrangement (2.5%). In 99% of cases (99/100), at least one clonal TCRB rearrangement was detected by PCR in the SB-positive cases. A predominance of complete Vbeta-Jbeta rearrangements was seen in TCRalphabeta(+) T-cell malignancies and CD3-negative T-ALL (100 and 90%, respectively), whereas in TCRgammadelta(+) T-ALL, more incomplete Dbeta-Jbeta TCRB rearrangements were detected (73%). Our results underline the reliability of this new TCRB PCR method and its strategic applicability in clonality diagnostics of lymphoproliferative disorders and MRD studies.  相似文献   
994.
The clinically most suitable method for minimal residual disease (MRD) detection in chronic lymphocytic leukemia is still controversial. We prospectively compared MRD assessment in 158 blood samples of 74 patients with CLL after stem cell transplantation (SCT) using four-color flow cytometry (MRD flow) in parallel with consensus IgH-PCR and ASO IgH real-time PCR (ASO IgH RQ-PCR). In 25 out of 106 samples (23.6%) with a polyclonal consensus IgH-PCR pattern, MRD flow still detected CLL cells, proving higher sensitivity of flow cytometry over PCR-genescanning with consensus IgH-primers. Of 92 samples, 14 (15.2%) analyzed in parallel by MRD flow and by ASO IgH RQ-PCR were negative by our flow cytometric assay but positive by PCR, thus demonstrating superior sensitivity of RQ-PCR with ASO primers. Quantitative MRD levels measured by both methods correlated well (r=0.93). MRD detection by flow and ASO IgH RQ-PCR were equally suitable to monitor MRD kinetics after allogeneic SCT, but the PCR method detected impending relapses after autologous SCT earlier. An analysis of factors that influence sensitivity and specificity of flow cytometry for MRD detection allowed to devise further improvements of this technique.  相似文献   
995.
996.
BACKGROUND: Elimination of immature thymocytes resulting in thymic atrophy is characteristic of acute graft-versus-host disease (aGVHD). Because aGVHD has been associated with elevated glucocorticoid (GC) production, and CD4,CD8 double-positive thymocytes undergo rapid apoptosis in response to GCs, we hypothesized that administration of the GC receptor antagonist RU486 (mifepristone) should alter aGVHD-mediated thymocyte apoptosis. METHODS: Thymic development in the presence of aGVHD was studied in a haploidentical nonirradiated murine transplantation model (C57BL/6-->B6D2F1). Recipients were treated with RU486 or vehicle alone. Thymic development was analyzed by flow cytometry at different times post transplant. RESULTS: Acute thymic GVHD was characterized (1) by infiltration of mature donor-derived T cells and (2) by increased apoptosis of immature CD4+CD8+ thymocytes between 1 and 2 weeks after allogeneic transplantation. Contrary to expectations, administration of RU486 had no effect on these two parameters. CONCLUSIONS: Our data suggest that thymic pathology during aGVHD is mediated via a glucocorticoid-independent mechanism of apoptosis as blockade of glucocorticoid receptors did not alter the GVHD-induced thymic phenotype.  相似文献   
997.
As the quality of water in dialysis fluid varies considerably, dialysate is often contaminated by large amounts of bacteria and endotoxins. Membrane properties and operating pressures are acknowledged to give high-flux dialysis with bicarbonate the bacteriological potential to favor passage of endotoxin fragments from the dialysate into the blood stream. Therefore, a sterile dialysate will have to become a standard. Ultrafiltration across hydrophobic synthetic membranes was shown to remove endotoxins (and their fragments) from dialysis water by the combined effect of filtration and adsorption. However, each module can be used for a limited time only. Ceramic membranes may represent an alternative to polymeric membranes for endotoxin removal. In this article, we tested the capacity of different commercial ceramic membranes with nominal molecular weight cut-off down to 1,000 to retain endotoxins from Ps. aeruginosa. The tested membranes did not generally produce dialysate meeting the Association for the Advancement of Medical Instrumentation standard. When using aluminum-containing membranes, we detected aluminum leaking into the dialysate that could possibly be transported into the blood stream.  相似文献   
998.
PURPOSE: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM-1) has recently been implicated in cancer development and progression. This study was performed to assess whether CEACAM-1 expression in primary tumors is correlated to long-term survival in patients with operable non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Primary tumors of 145 consecutive patients with completely resected NSCLC (pT(1-4) pN(0-2) M(0) R(0)) were stained immunohistochemically using the monoclonal anti-CEACAM-1 antibody 4D1/C2. The prognostic relevance of CEACAM-1 expression was evaluated by univariate Kaplan-Meier and multivariate Cox regression analysis. The median follow-up period was 72 months (range, 10-130 months). RESULTS: Normal bronchiolar epithelium present in all sections exhibited no immunostaining. In contrast, 73 tumors (50.4%) showed between 1 and 66% CEACAM-1 positive tumor cells, and 72 tumors (49.6%) exhibited even a higher percentage of positive tumor cells. A high CEACAM-1 expression rate (i.e., >/=66% positive tumor cells) was more frequent in adenocarcinomas than in squamous cell carcinomas (61.9 versus 35.7%, respectively). Multivariate Cox regression analysis demonstrated that CEACAM-1 represents an independent prognosticator for cancer-related survival (P = 0.018; relative risk, 1.8; 95% confidence interval, 1.1-2.8). Subgroup analysis revealed that a high CEACAM-1 expression rate was of significant prognostic impact in pN(1)-pN(2) patients (n = 60; P = 0.024), pT(3)-pT(4) patients (n = 22; P = 0.009), and stage IIa-IIIa patients (n = 69; P = 0.012). CONCLUSIONS: The absence of CEACAM-1 in normal lung tissue and its expression in tumor cells argues against a tumor-suppressive role of CEACAM-1 in NSCLC. The correlation between elevated CEACAM-1 expression and an unfavorable prognosis indicates rather that CEACAM-1 might promote lung cancer progression.  相似文献   
999.
PURPOSE: CEACAM6, CEACAM1, and human carcinoembryonic antigen (CEA) are coexpressed in normal colorectal epithelia, but show deregulated expression in colorectal cancers (CRC). Upregulation of CEACAM6 expression in hyperplastic polyps and early adenomas represents one of the earliest observable molecular events leading to colorectal tumors. The aim of our study was to evaluate the prognostic relevance of CEACAM6, CEACAM1, and CEA tissue expression in patients with CRC. PATIENTS AND METHODS: Immunohistochemical analysis was carried out on tissue microarrays from 243 paraffin-embedded biopsies from a randomized controlled clinical trial (Swiss Group for Clinical Cancer Research [SAKK] 40/81) of adjuvant fluorouracil-based chemotherapy with CEACAM-specific monoclonal antibodies. The median follow-up was 8 years. Overall survival (OS) and disease-free survival (DFS) were calculated using Kaplan-Meier estimates and hazard ratios (HRs) estimated using Cox proportional hazards models. RESULTS: Tissue expression of CEACAM6, CEACAM1, and CEA was enhanced in 55%, 58%, and 94% of patients, respectively. Multivariate Cox analysis including sex, age, tumor site, stage, differentiation grade, treatment, and nodal status as covariates showed that CEACAM6 overexpression independently predicted poor OS (HR, 1.86; P =.0100) and DFS (HR, 2.00; P =.0028), whereas CEACAM1 or CEA were not significantly related to these outcomes. The data did not provide evidence for or against the hypothesis that the CEACAM6 effect on survival differs according to treatment. CONCLUSION: Expression of the cell adhesion molecule CEACAM6 in CRC is an independent prognostic factor allowing subdivision of patients into low- and high-risk groups. Whether CEACAM6 or CEA and CEACAM1 might be useful as predictive markers of chemotherapy benefit remains unclear.  相似文献   
1000.
OBJECTIVE: The purpose of this randomized controlled trial was to evaluate the benefits of compression and walking exercises in comparison with bed rest in the acute stage of proximal deep venous thrombosis (DVT). METHODS: Forty-five patients with proximal DVT that was proved with compression ultrasound scan or phlebography were randomized into three groups. Group A consisted of 15 patients who received inelastic compression bandages (Unna boots on the lower leg, adhesive bandages on the thigh), and group B consisted of 15 patients who received thigh-length compression stockings, class II. Group C consisted of 15 patients who underwent bed rest and no compression. All patients received dalteparin, 200 IU/kg per body weight, subcutaneously every 24 hours. The clinical characteristics of the three groups were comparable. Primary end points were the reduction of pain assessed daily with the Visual Analogue Scale and the Lowenberg test, the reduction of leg circumference at the ankle and calf levels, and the improvement of clinical scores. The daily walking distance was measured with a pedometer. Safety parameters were ventilation-perfusion scans and duplex ultrasound scans performed on days 0 and 9. RESULTS: The daily walking distance was between 600 and 12,000 m in the compression groups and averaged 66 m in the bed rest group. The pain level showed a statistically significant reduction starting after the second day in the compression groups (A and B) and after 9 days in the bed rest group C (P <.05). The same was true for the measurement of leg circumference. Improvement of the clinical scores was significantly better in the compression groups compared with the bed rest group (P <.01). There was no significant difference concerning the occurrence of new pulmonary emboli and regression of thrombus diameter. Progression of thrombi in the femoral vein was greater and occurred more frequently in the bed rest group than in the other two groups (P = not significant). CONCLUSION: Mobile patients with acute proximal DVT treated with low molecular weight heparin should be encouraged to walk with compression bandages or medical compression stockings. The rate of resolution of pain and swelling is significantly faster when the patient ambulates with compression. The risk of pulmonary embolism is not significantly increased by this approach.  相似文献   
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