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131.
Delineation of brain tumor extent with [11C]L-methionine positron emission tomography: local comparison with stereotactic histopathology. 总被引:9,自引:0,他引:9
Lutz W Kracht Hrvoje Miletic Susanne Busch Andreas H Jacobs Jurgen Voges Moritz Hoevels Johannes C Klein Karl Herholz Wolf-D Heiss 《Clinical cancer research》2004,10(21):7163-7170
PURPOSE: Methyl-[11C]L-methionine ([11C]MET) positron emission tomography (PET) in brain tumors reflects amino acid transport and has been shown to be more sensitive than magnetic resonance imaging in stereotactic biopsy planning. It remains unclear whether the increased [11C]MET uptake is limited to solid tumor tissue or even detects infiltrating tumor parts. EXPERIMENTAL DESIGN: In 30 patients, a primary or recurrent brain tumor was suspected on magnetic resonance imaging. Patients were investigated with [11C]MET-PET before stereotactic biopsy. The biopsy trajectories were plotted into the [11C]MET-PET images with a newly designed C-based software program. The exact local [11C]MET uptake was determined within rectangular regions of interest of 4 mm in width and length aligned with the biopsy specimen. Individual histologic specimens were rated for the presence of solid tumor tissue, infiltration area, and nontumorous tissue changes. RESULTS: Receiver operating characteristics analysis demonstrated a sensitivity of 87% and specificity of 89% for the detection of tumor tissue at a threshold of 1.3-fold [11C]MET uptake relative to normal brain tissue. At this threshold, only 13 of 100 tumor positive specimen were false negative mainly in grade 2 astrocytoma. In grade 2 astrocytoma, mean [11C]MET uptake in the infiltration area was significantly higher than in solid tumor tissue (P < 0.003). CONCLUSIONS: [11C]MET-PET detects solid parts of brain tumors, as well as the infiltration area at high sensitivity and specificity. High [11C]MET uptake in infiltrating tumor of astrocytoma WHO grade 2 reflects high activity in this tumor compartment. Molecular imaging, with [11C]MET, will guide improved management of patients with brain tumors. 相似文献
132.
Patient-controlled intranasal analgesia: effective alternative to intravenous PCA for postoperative pain relief 总被引:2,自引:0,他引:2
Susanne Toussaint MD DEAA Julia Maidl MD Rolf Schwagmeier MD Hans Walter Striebel MD PhD DEAA 《Journal canadien d'anesthésie》2000,47(4):299-302
PURPOSE: To investigate whether the nasal route for fentanyl administration in patient-controlled analgesia (PCA) provides as effective postoperative analgesia as intravenous PCA. METHODS: Patient-controlled intranasal or intravenous analgesia with fentanyl was investigated in 48 patients (ASA I-III) on the day of surgery (orthopedic, abdominal or thyroid) in a prospective, randomized, double-blind, double-dummy study. Fentanyl was given in a bolus of 25 microg for intranasal and 17.5 microg for i.v. PCA, lockout interval six minutes. The first requested dose was doubled in both groups. Pain intensity (101-point numerical rating scale) and vital parameters were observed at 11 measurement points during the 240 min study. Patients were asked for side effects at every measurement point and for their satisfaction at the end of the study by the same investigator (J.M.). RESULTS: Onset of analgesia, the first reduction in pain intensity on the numerical rating scale, was 21 +/- 11 min (range 15-45 min) in intranasal and 22 +/- 16 min (range 15-90 min) in i.v. PCA. Pain intensity was reduced from 55 +/- 11 to 11 +/- 10 in the intranasal group and from 53 +/- 8 to 11 +/- 6 in the i.v. PCA group. Vital parameters remained stable and side effects were comparable in both groups. The judgement "excellent" or "good" was given by 21 of 23 patients treated intranasally and 24 of 25 patients treated intravenously. CONCLUSION: Intranasal PCA with fentanyl was an effective alternative to i.v. PCA in postoperative patients. 相似文献
133.
Torsten Haferlach Claudia Schoch Helmut L?ffler Winfried Gassmann Wolfgang Kern Susanne Schnittger Christa Fonatsch Wolf-Dieter Ludwig Christian Wuchter Brigitte Schlegelberger Peter Staib Albrecht Reichle Uschi Kubica Hartmut Eimermacher Leopold Balleisen Andreas Grüneisen Detlef Haase Carlo Aul Jochen Karow Eva Lengfelder Bernhard W?rmann Achim Heinecke Maria Cristina Sauerland Thomas Büchner Wolfgang Hiddemann 《Journal of clinical oncology》2003,21(2):256-265
PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account. 相似文献
134.
Elevated expression level of survivin protein in soft-tissue sarcomas is a strong independent predictor of survival. 总被引:17,自引:0,他引:17
Matthias Kappler Matthias Kotzsch Frank Bartel Susanne Füssel Christine Lautenschl?ger Uta Schmidt Peter Würl Matthias Bache Hannelore Schmidt Helge Taubert Axel Meye 《Clinical cancer research》2003,9(3):1098-1104
PURPOSE: Survivin is a member of the inhibitor-of-apoptosis gene family and is known to be overexpressed in a number of tumor types. The aim of this study was to evaluate the prognostic value of survivin protein expression in tumor tissue extracts in a group of well-characterized soft-tissue sarcoma (STS) patients. EXPERIMENTAL DESIGN: In this investigation, malignant tissue samples from 63 STS patients as well as from a panel of tumor cell lines were investigated, with nonmalignant tissues serving as controls. The survivin protein level was quantified by a novel ELISA and by Western blot analysis. Results obtained by both methods were compared with clinicopathological parameters regarding tumor grade and tumor entity, and they were then correlated to survival in a multivariate Cox regression model. RESULTS: High survivin levels were detected by ELISA and Western blot analysis in tumor tissue extracts and in lysates of tumor cell lines. None or only weak expression of survivin protein was found in nonmalignant cells and tissues. When comparing survivin values obtained by ELISA or Western blot, we found a significant correlation between both methods (P = 0.013, Pearson test). Our findings revealed that, in multivariate Cox regression analyses, survivin levels measured by ELISA and Western blot were significantly associated with tumor-related death in STS patients (P = 0.001, RR = 19.8, and P = 0.004, RR = 5.1, respectively). However, in a direct comparison of both survivin protein detection assays, we found a higher sensitivity and a stronger correlation to prognosis in survivin ELISA as compared with the Western blot assays. Furthermore, a higher tumor grade and more aggressive STS entity showed an elevated survivin protein expression level. CONCLUSION: Altogether, an elevated survivin content in tumor tissue extracts has a significant and independent negative predictive value on the survival-rate of STS patients. This finding corresponds well to data obtained for the mRNA level of survivin, as shown previously (M. Kappler et al., Int. J. Cancer, 95: 360-363, 2001). 相似文献
135.
Peter Albers Roswitha Siener Sabine Kliesch Lothar Weissbach Susanne Krege Christoph Sparwasser Harald Schulze Axel Heidenreich Werner de Riese Volker Loy Erhard Bierhoff Christian Wittekind Rolf Fimmers Michael Hartmann 《Journal of clinical oncology》2003,21(8):1505-1512
PURPOSE: To prospectively assess potential risk factors for relapse in clinical stage I nonseminomatous germ cell tumors of the testis (CS I NSGCT). PATIENTS AND METHODS: From September 1996 to May 2002, 200 patients with CS I NSGCT were prospectively assigned to retroperitoneal lymph node dissection (RPLND), and risk factor assessment was performed within a multicenter protocol. One hundred sixty-five patients had an adequate minimum follow-up of 12 months (mean, 34.5 months) or had pathologic stage II. RESULTS: Pathologic stage II disease was found in 27.9% of patients. Only 0.6% of patients relapsed in the retroperitoneum after confirmation of pathologic stage I disease. With reference pathology, vascular invasion (VI) was most predictive of stage in multifactorial analysis (accuracy, 65.1%). However, the positive predictive value (PPV) of VI to predict patients who have metastatic disease or relapse during follow-up was only 52.7%. With absent VI, low-risk patients had a negative predictive value (NPV) of 76.9%. With a combination of several risk factors, the PPV increased to 63.6% and the negative predictive value increased to 86.5%. CONCLUSION: Even with an optimal combination of prognostic factors and reference pathology, more than one third of patients predicted to have pathologic stage II or relapse during follow-up will not harbor metastatic disease and, therefore, would be overtreated with adjuvant therapy. However, patients at low risk may be predicted at an 86.5% level, and thus, surveillance in highly compliant patients would be a valuable option. For high-risk patients, further reduction of adjuvant treatment is necessary. 相似文献
136.
137.
138.
Susanne Kimeswenger Ruth Dingelmaier‐Hovorka Dagmar Foedinger Christian Jantschitsch 《Experimental dermatology》2018,27(3):276-279
The exact correlation between melanoma and sun‐light is still a controversially debated issue. Although natural sunlight contains various ratios of UVA and UVB, most investigators so far focused on the effects of single solar wavebands and neglected possible interactions. Therefore, in this study primary human melanocytes of three donors were simultaneously exposed to physiologic doses of UVA1 and UVB. Effects on apoptosis were analysed using annexin V assays and cell death ELISAs, and effects on DNA damage were investigated using southwestern slot blots. While UVA1 did not influence UVB‐induced apoptosis, UVA1 impaired the repair of UVB‐induced cyclobutane pyrimidine dimers (CPD) as the amount of CPD was 1.8 times higher in UVA1 + UVB than in UVB only exposed melanocytes six hours after irradiation. We conclude that UVA1 might contribute to melanomagenesis as it partially inhibits the repair of UVB‐induced CPD in human melanocytes while it does not affect UVB‐mediated apoptosis. 相似文献
139.
Increased proportions of B cells with spontaneous production of interleukin‐10 in HIV‐infected individuals are normalized during combination antiretroviral therapy: a longitudinal study
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Camilla Sambleben Andreas Dehlbæk Knudsen Hans J. Hartling Claus H. Nielsen Susanne D. Nielsen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2018,126(2):143-151
Interleukin‐10 (IL‐10)‐producing B cells (B10 cells) may inhibit HIV‐specific T cells and are elevated in untreated HIV infection. We aimed to determine the effect of combination antiretroviral treatment (cART) on the proportion of B10 cells. Furthermore, we compared B10‐cell proportions in HIV‐infected progressors and viremic controllers. This was a prospective study including HIV‐infected progressors, viremic controllers and healthy controls. Progressors initiating cART were followed for 6 months. Purified B cells were stimulated with CpG, alone or in combination with HIV gp120, and the proportion of B10 cells was measured by flow cytometry. Without stimulation, the B10‐cell proportion was higher in progressors than in healthy controls, while viremic controllers and healthy controls had comparable proportions. Moreover, the proportion of CD24hiCD38hi transitional B cells was higher in progressors than in healthy controls. After initiation of cART, the proportion of B10 cells and transitional B cells decreased. In conclusion, progressors had elevated B10‐cell proportions, while viremic controllers displayed normal proportions. After initiation of cART, the B10‐cell proportion decreased. This could limit B10‐cell‐mediated suppression of specific CD8+ T‐cell responses. 相似文献