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Oystein Bakkevig Siri Steine Kari von Hafenbrädl Even Lærum 《Scandinavian journal of primary health care》2013,31(4):247-251
Objective - To evaluate whether measurement of albumin creatinine ratio (ACR) on a spot urine specimen can replace a timed overnight collection of urine albumin excretion rate (UAER) in patients with diabetes in primary care. Design - Patients with diabetes attending Rønvik Health Centre were asked to bring a timed overnight collection of urine for measurement of UAER. They were also asked to void a urine specimen for measurement of albumin creatinine ratio. Setting - Primary health care. Subjects - One-hundred-and-six persons with diabetes (47 women, 59 men) aged 13 to 78 years. Results - The sensitivity and specificity of ACR with cut-off values of 2.5 mg/mmol for men and 3.5 mg/mmol for women compared to UAER with cut-off value of 20 mg/24 h was 90%. Conclusions - Spot urine ACR analysed on a DCA 2000 can replace a timed (overnight) collection of urine and measurement of UAER when diabetic patients are reviewed in general practice. This simplifies procedures for the patient as a timed urine collection is no longer necessary. Another advantage is that the results are available after 7 min. 相似文献
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Hatfield K Ryningen A Corbascio M Bruserud O 《International journal of cancer. Journal international du cancer》2006,119(10):2313-2321
Interactions between acute myelogenous leukemia (AML) blasts and neighbouring endothelial cells in the bone marrow seem important both for disease development and susceptibility to chemotherapy. We investigated the effects of soluble mediators released by microvascular endothelial cells on native human AML cells. AML cells derived from 33 patients were cocultured with microvascular endothelial cells, separated by a semipermeable membrane. We investigated the effect of coculture on AML cell proliferation, viability/apoptosis and cytokine release. Coculture increased AML cell proliferation, and this growth enhancement included the clonogenic leukemia cell subset. Increased release of several soluble mediators was also detected (interleukin 3, interleukin 6, granulocyte-macrophage and granulocyte colony-stimulating factors) in cocultures. Our cytokine neutralization experiments suggest that an intercellular crosstalk involving several soluble mediators contribute to the increased leukemia cell proliferation. The presence of endothelial cells had an additional antiapoptotic effect on the AML cells. The endothelial cells did not have any growth-enhancing effect on native human acute lymphoblastic leukemia cells. Our in vitro results suggest that the release of soluble mediators by microvascular endothelial cells supports leukemic hematopoiesis through paracrine mechanisms by direct enhancement of AML blast proliferation and by inhibition of leukemic cell apoptosis. 相似文献
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BACKGROUND: Approximately 20% of the breast carcinoma cases detected on mammography screening represent ductal carcinoma in situ (DCIS). Cytopathologists are exposed to cytologic material from DCIS when nonpalpable, mammographic lesions are aspirated during the workup of organized and opportunistic mammography screening. METHODS: The material in the current study was comprised of 225 representative fine-needle aspiration cytology (FNAC) smears from histologically confirmed DCIS of the breast that were diagnosed between 1990-2003. Smears were rescreened to search for the following features: nuclear size (grading), monolayer sheets, solid and cribriform epithelial aggregates, micropapillary and true papillary structures, comedo-type necrosis, microcalcifications, myoepithelial cells, and discohesion. RESULTS: There were 174 high-grade lesions (77% were Grade 3) and 51 nonhigh-grade lesions (Grades 1 and 2). The concordance between the cytologic and histologic grading was 97% in the Grade 3 lesions and 94% in the Grade 1/2 lesions. Smears from Grade 3 DCIS contained solid and/or cribriform epithelial aggregates in > 93%% of the cases, whereas smears from Grade 1/2 lesions were found to contain cribriform aggregates in 94% of the cases. Pure subtypes were virtually nonexistent. Monolayer sheets were found in 49% of nonhigh-grade DCIS and in 16% of high-grade DCIS. Myoepithelial cells were demonstrated in 51% of the nonhigh-grade DCIS lesions and 27% of the Grade 3 lesions. Microcalcifications were found on the smears from 96% of nonhigh-grade lesions and 84% of high-grade lesions. Approximately 47% of high-grade DCIS and 31% of nonhigh-grade DCIS were found to harbor a distinct single cell population. CONCLUSIONS: The findings on FNAC from DCIS of the breast completely mirror the histologic heterogeneity of growth pattern subtypes. Primary cytologic grading can effectively separate the high-grade lesions from the nonhigh-grade lesions. 相似文献
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Bone marrow micrometastases in advanced stage non-small cell lung carcinoma patients 总被引:1,自引:0,他引:1
Brunsvig PF Flatmark K Aamdal S Høifødt H Le H Jakobsen E Sandstad B Fodstad O 《Lung cancer (Amsterdam, Netherlands)》2008,61(2):170-176
BACKGROUND: The clinical relevance of bone marrow micrometastases in non-small cell lung cancer (NSCLC) is undetermined, and the value of such analyses in advanced stage patients has not been assessed previously. METHODS: Immunomagnetic selection with the MOC31 (anti-EpCam) antibody was performed to isolate and detect tumor cells in bone marrow aspirates obtained from 196 patients with NSCLC, and the patients were subjected to follow-up for the assessment of survival. Repeated bone marrow samples, 2-7 samples per patient, were obtained from 13 long-term survivors. RESULTS: MOC31 positive tumor cells were detected in 107 of 196 (55%) samples, a frequency similar to results reported in low-stage patients prior to curative surgical resection for NSCLC. No association was found between the presence of bone marrow micrometastases and disease stage or histological subgroup, and survival was similar in patients with and without detectable tumor cells in bone marrow. Repeated bone marrow analysis revealed, for the first time in this group of patients, the continued presence of tumor cells regardless of the given therapy and treatment response. CONCLUSION: The immunomagnetic method utilized is a feasible strategy for the detection of bone marrow micrometastases in NSCLC. In advanced stage patients, the presence of MOC31 positive cells in bone marrow does not predict survival. Repeated analyses of bone marrow samples from long-term survivors revealed tumor cells in bone marrow which may represent dormant cells of particular interest for further characterization and follow-up. 相似文献
48.
Several previous studies have demonstrated that both conventional cytotoxic drugs as well as targeted therapeutics can induce apoptosis in primary human acute myelogenous leukemia (AML) cells. However, the apoptotic phenotype of dying AML cells has been less extensively characterized. Even though specific antileukemic immune reactivity is important in AML, especially for allotransplanted patients, it has not been investigated whether dying primary human AML cells show phenotypic characteristics consistent with immunogenic apoptosis [calreticulin exposure, heat shock protein (HSP) release]. We therefore investigated whether in vitro cultured primary human acute myeloid leukemia (AML) cells show calreticulin exposure and HSP70/HSP90 release during spontaneous (stress-induced) apoptosis when cultured in medium alone and when cultured in the presence of antileukemic drugs. Both surface exposure of calreticulin and release of HSP70 and HSP90 was detected but showed a wide variation between patients. This variation was also maintained when the AML cells were cultured in the presence of cytotoxic drugs (cytarabine, daunorubicin, mitomycin), all-trans retinoic acid (ATRA) and valproic acid. Finally, AML cells collected during in vivo ATRA therapy showed increased calreticulin exposure during spontaneous in vitro apoptosis, suggesting that in vivo pharmacotherapy can modulate the apoptotic phenotype. To conclude, apoptotic AML cells can show phenotypic characteristics consistent with immunogenic apoptosis, but there is a wide variation between patients and the level of calreticulin exposure/HSP release seems to depend on individual patient characteristics rather than the apoptosis-inducing agent. 相似文献
49.
Liu H Tekle C Chen YW Kristian A Zhao Y Zhou M Liu Z Ding Y Wang B Mælandsmo GM Nesland JM Fodstad O Tan M 《Molecular cancer therapeutics》2011,10(6):960-971
In many types of cancer, the expression of the immunoregulatory protein B7-H3 has been associated with poor prognosis. Previously, we observed a link between B7-H3 and tumor cell migration and invasion, and in present study, we have investigated the role of B7-H3 in chemoresistance in breast cancer. We observed that silencing of B7-H3, via stable short hairpin RNA or transient short interfering RNA transfection, increased the sensitivity of multiple human breast cancer cell lines to paclitaxel as a result of enhanced drug-induced apoptosis. Overexpression of B7-H3 made the cancer cells more resistant to the drug. Next, we investigated the mechanisms behind B7-H3-mediated paclitaxel resistance and found that the level of Stat3 Tyr705 phosphorylation was decreased in B7-H3 knockdown cells along with the expression of its direct downstream targets Mcl-1 and survivin. The phosphorylation of Janus kinase 2 (Jak2), an upstream molecule of Stat3, was also significantly decreased. In contrast, reexpression of B7-H3 in B7-H3 knockdown and low B7-H3 expressing cells increased the phosphorylation of Jak2 and Stat3. In vivo animal experiments showed that B7-H3 knockdown tumors displayed a slower growth rate than the control xenografts. Importantly, paclitaxel treatment showed a strong antitumor activity in the mice with B7-H3 knockdown tumors, but only a marginal effect in the control group. Taken together, our data show that in breast cancer cells, B7-H3 induces paclitaxel resistance, at least partially by interfering with Jak2/Stat3 pathway. These results provide novel insight into the function of B7-H3 and encourage the design and testing of approaches targeting this protein and its partners. 相似文献
50.
AIM: The purpose of the study was to evaluate the ability of CT, including expiratory scans with minimum intensity projection in predicting the development of bronchiolitis obliterans syndrome after lung transplantation. MATERIALS AND METHODS: Forty consecutive patients, 29 bilateral and 11 single lung transplanted, were followed-up with regular scans for a median of 36 months. Air trapping was evaluated on expiratory scans constructed from two short spiral scans with minimum intensity projection-technique, one at the level of the carina and the other midway between the right diaphragm and the carina. Air trapping was scored on a 16-point scale. Bronchiolitis obliterans syndrome was diagnosed according to established clinical criteria and quantified spirometrically. RESULTS: Bronchiolitis obliterans syndrome developed in 17 patients (43%) after a median of 12 months. Air trapping and bronchiectasis was seen before the diagnosis of bronchiolitis obliterans syndrome in only two and one patient, respectively. Interobserver agreement for air trapping score was good (kappa = 0.65). Air trapping scores performed significantly better than that achieved by chance alone in determining the presence of bronchiolitis obliterans syndrome (P = 0.0025). An air trapping score of 4 or more provided the best results with regard to sensitivity and specificity in diagnosing bronchiolitis obliterans syndrome. The sensitivity, specificity, positive and negative predictive values of an air trapping of 4 or more in the diagnosis of bronchiolitis obliterans syndrome were 77, 74, 68 and 81%, respectively. CONCLUSION: Expiratory CT scans with minimum intensity projection-reconstruction did not predict the development of bronchiolitis obliterans syndrome in most patients. The findings seriously limit the clinical usefulness of long-term CT monitoring for diagnosing bronchiolitis obliterans syndrome after lung transplantation. 相似文献