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91.
The presence of natural carbohydrate-binding antibodies may play a role in host defence against malignant cells in addition to elicitation of an immune response by artificial carbohydrate antigens. Human serum contains immunoglobulin G(2) (IgG) fractions with selectivity to alpha- and to beta-galactosides, respectively, irrespective of the type of blood group of the donor. To determine whether these naturally occurring subfractions may have any relevance for tumor disease control, their binding to malignant cells was ascertained by cytofluorimetric assays in vitro with a number of human tumor cell lines of different histogenetic origin. The affinity of cell binding was comparable to that of binding to lactosylated or melibiosylated neoglycoconjugates as model ligands in solid-phase assays and K-D values were found to be in the range of 5-300 nM. Cross-reactivity of the anomer-selective subfractions to the other type of ligand was observed to be rather low. When the IgG contents of plasma samples of patients with diverse types of lung cancer were assessed, the concentrations of both galactoside-binding immunoglobulin G subfractions were significantly increased in association with presence of small cell lung carcinoma and of metastatic lesions to the lung without any marked change in the overall IgG plasma level. Such an apparently general enhancement was seen for patients with adenocarcinoma and included both subfractions with no impact on their percentage in the total IEC content. When detergent extracts of tumor and tumor-free specimens of the same patient were analyzed with the affinity purified antibody subfractions to comparatively determine ligand presentation, increases in sugar-inhibitable binding were especially noted for the tumor tissue of small cell lung carcinomas and apparently tumor-free samples of cases with lung metastasis. Material from other types of lung cancer revealed no significant indication for disease-related alterations with the exception of carcinoids. These data demonstrate that plasma levels and ligand expression for two types of natural galactoside-binding immunoglobulin G fractions can show nonuniform responses in patients within the class of lung cancer. They encourage to deliberately monitor these parameters of the natural carbohydrate-directed antibody fractions in cancer patients with various types of disease to clarify the clinical significance of respective malignancy-associated changes. 相似文献
92.
Angelika Krämer Wolfgang Saeger Gesche Tallen Dieter K. Lüdecke 《Endocrine pathology》1994,5(4):198-211
To assess the proliferative activity of pituitary adenomas, 36 surgically removed adenomas were studied by light microscopical parameters; mitotic count; expression of PCNA, Ki-67, cathepsin D, and EGF; and image cytometry. Three adenomas (9%) showed high, 11 (34%) medium, 17 (53%) moderate, and 1 (3%) low structural differentiation. In 10 adenomas (31%), no mitosis was observed. The average was 2.4 mitoses/100 HPF; the highest count was 7.1 mitoses/100 HPF. Eleven adenomas (33.3%) were PCNA-negative; in 20 adenomas (60.6%), between 0.05 and 3.9, and in 2 adenomas (6.0%), between 10.5 and 16.4 PCNA-positive nuclei were observed. Only a recurrent null-cell adenoma (9%) was Ki-67-negative. Three adenomas (9.1%) were EGF-negative, 28 (84.8%) showed up to 10% positive cells, and 2 (6.1 %) showed between 10 and 30% positive cells; 19 adenomas (68%) were cathepsin D-negative, including all endocrine-inactive adenomas. Half the adenomas had an euploid DMA stem line. Endocrine-inactive adenomas displayed a higher rate of euploid DNA stem lines than endocrine-active adenomas. The S-phase fraction varied between 2.97 and 28%, with a mean value of 14.4%. Half the adenomas showed an S-phase fraction of 11.65% or lower. 相似文献
93.
Human phase I vaccine trials of 3 recombinant asexual stage malaria antigens with Montanide ISA720 adjuvant 总被引:13,自引:0,他引:13
Allan Saul Gregor Lawrence Anne Smillie Christine M. Rzepczyk Carol Reed Darrin Taylor Karen Anderson Anthony Stowers Richard Kemp Anthony Allworth Robin F. Anders Graham V. Brown David Pye Peter Schoofs David O. Irving Shanny L. Dyer Graeme C. Woodrow William R. S. Briggs Rosemaria Reber Dieter Stürchler 《Vaccine》1999,17(23-24):3145-3159
Two phase I vaccine trials were conducted to test the immunogenicity and safety of a vaccine containing three recombinant malaria antigens from the asexual stage of Plasmodium falciparum. The three antigens are a fragment of MSP1 (190LCS.T3); MSP2 and a portion of RESA and were formulated in Montanide ISA720 adjuvant. These trials investigated the dose response of each antigen for eliciting both antibody and T-cell responses and the immunogenicity of a mixture of the antigens compared with the antigens injected separately. All three antigens elicited both antibody and T-cell responses. Strong T-cell responses were observed with 190LCS.T3 and RESA with stimulation indices exceeding 100 for peripheral blood leucocytes in some individuals. The antibody responses were generally weak. The human antibody responses observed with MSP2 in Montanide ISA720 were not significantly different from those obtained in an earlier trial which used MSP2 with alum as the adjuvant. No antigenic competition was observed: volunteers receiving a mixture of antigens had similar responses to those receiving the three antigens at separate sites. Tenderness and pain at the injection site were common over the first few days following immunization. In some volunteers, especially those receiving the highest doses tested, there was a delayed reaction at the injection site with pain and swelling occurring approximately 10 days after injection. 相似文献
94.
Christian M. Kurbacher Ian A. Cree Ursula Brenne Howard W. Bruckner Jutta A. Kurbacher Peter Mallmann Peter E. Andreotti Dieter Krebs 《Breast cancer research and treatment》1996,41(2):161-170
Summary Apart from clinical trials, mitoxantrone (MX) is rarely used in breast cancer (BC) due to the anticipated anthracycline cross-resistance. We have examined this drug versus doxorubicin (DOX) using data obtained fromin vitro microplate ATP tumor chemosensitivity assays (ATP-TCA) of BC cells which were derived from 55 chemotherapy-naive patients at time of primary surgery. Both drugs were tested at 6 different concentrations ranging from 6.25% to 200% peak plasma concentrationin vivo (PPC). Differences between DOX and MX observed for mean IC50, IC90, and a sensitivity index (SI) were not statistically significant.In vitro response rates were 44% for DOX and 52% for MX. 34 of 52 eligible assays (65%) showed comparable activity of both drugs whereas a lack of cross-resistance was observed in the remaining 18 (35%) tumors as indicated by differences for SI. Cumulative concentration-response plots of tumors respondingin vitro with a 50 percent or 90 percent tumor cell inhibition showed a strong dose-dependence for both DOX and MX at concentrations which normally can be achieved within clinical tumors (i.e. 6.25%-50% PPC). At higher concentrations, however, cytotoxicity of DOX and MX could not be improved by furtherin vitro dose escalation. Moreover, a substantial proportion of BC specimens (DOX: 48.1%; MX: 40.4%) did not experience a 90 tumor cell inhibition at 200% PPC. In conclusion,in vitro results obtained by ATP-TCA indicate that there is no cross-resistance between MX and DOX in a substantial proportion of BC patients. This may be clinically useful and suggests that combinations including MX should be tested in patients clinically resistant to DOX containing regimens. Since both drugs produced sigmoidal concentration-response curves, dose escalation beyond a certain point may not produce increased sensitivity. 相似文献
95.
In the Surgical Department of the University of Erlangen, 307 reconstructions in all areas of the arterial tree were performed with PTFE (GORE-TEX®) grafts, of which 188 were performed in the femoral-popliteal and femoral-crural areas. Femoral-popliteal bypass grafts above the knee joint remained patent in 93% of the patients during an average follow-up time of 6.7 months. Below the knee joint, the patency rate was 85% during an average follow-up time of 5.6 months. In the proximal aorta, aorta-renal, and aorta-femoral areas, long-term results with the PTFE graft have been excellent. 相似文献
96.
Dieter St?hr 《Brain topography》1991,3(4):457-469
Proceedings
Fourth swiss EEG-EP mapping meeting 相似文献97.
Ulrich Schwabe Volker Lenschow Dieter Ukena David R. Ferry Hartmut Glossmann 《Naunyn-Schmiedeberg's archives of pharmacology》1982,321(1):84-87
Summary N6-p-Hydroxyphenylisopropyladenosine (HPIA) has been labelled with carrier-free Na[125I] to very high specific activity (2,175 Ci/mmol) and used as an agonist ligand to characterize Ri adenosine receptors in rat cerebral cortex membranes. The binding is saturable, reversible, stereospecific and dependent on protein concentration. The specific binding at 37°C was of high affinity with an equilibrium dissociation constant KD of 0.48 nmol/l and was saturable with 0.23 pmol of [125I]HPIA per mg of protein. The rate constant of association, k1, was 3.25×108 l mol–1 min–1 and that of dissociation, k2, 0.0110 min–1 yielding a t1/2 of 63 min. In competition experiments the (–)isomer of N6-phenylisopropyladenosine (PIA) was 16-fold more potent than the (+)isomer in competing for the binding sites. Specific binding was most effectively displaced by N6-cyclohexyladenosine (CHA, ki=0.26 nmol/l), (–)PIA (ki=0.33 nmol/l) and HPIA (ki=0.52 nmol/l), whereas 5-N-ethylcarboxamidoadenosine (NECA, ki-1.42 nmol/l) was less effective. The methylxanthines 3-isobutyl-1-methylxanthine (IBMX), theophylline and caffeine which have been classified as adenosine antagonists had ki values between 5–34 mol/l. Binding of [125I]HPIA was regulated by guanine nucleotides and divalent cations. The results indicate that [125I]HPIA labels Ri adenosine receptors in rat brain membranes. 相似文献
98.
Dieter Naber David Pickar Glenn C. Davis Robert M. Cohen David C. Jimerson Mary A. Elchisak Emanuel G. Defraites Ned H. Kalin Samuel C. Risch Monte S. Buchsbaum 《Psychopharmacology》1981,74(2):125-128
8 mg of naloxone were administered IV to 14 normal volunteers in a placebo-controlled, double-blind experiment. Plasma levels of -endorphin, cortisol, prolactin, growth hormone, HVA and MHPG were determined before and 45 min after administration. Naloxone elicited significant increases in cortisol and MHPG but did not change plasma levels of the other compounds. In an additional experiment on two subjects, 20 mg of naloxone caused elevations of -endorphin as well as of cortisol. This parallel increase indicates that the linkage between the secretion of -endorphin and ACTH/cortisol may be dose-dependent. The increase in MHPG is in agreement with the hypothesized association of noradrenergic hyperactivity and opiate withdrawal. 相似文献
99.
First experience with gamma probe guided sentinel lymph node surgery in penile cancer 总被引:3,自引:0,他引:3
Wawroschek F Vogt H Bachter D Weckermann D Hamm M Harzmann R 《Urological research》2000,28(4):246-249
Because of the curative approach, the detection of lymph node metastases in squamous cell carcinoma (SCC) of the penis is
of significant clinical relevance. Sentinel lymph node (SLN) identification by means of lymphangiography has been proven to
be insufficiently safe. However, the high morbidity of inguinal lymphadenectomy and the considerable individual variability
regarding the location of lymph node metastases justify the necessity of a technique that enables the identification of SLNs.
Since 1998, SLNs have been intraoperatively identified and selectively dissected, after peritumoral injection of technetium-99m
nanocolloid and using lymphoscintigraphy, in three patients (one with malignant melanoma and two with SCC). At least one SLN
could be detected in each patient. The maximum surgical time was 30 min. There were no severe complications. Lymph node metastases
did not occur in any patient. Upon a mean follow-up of 10 months, all patients are currently free of tumor. Owing to the long-term
results of sentinel lymphadenectomy in malignant melanoma of other locations and our preliminary results with respect to penile
carcinoma, we consider the current method appropriate as the only primary operation for lymph node staging in early stages
and, in combination with modified inguinal lymphadenectomy, in locally advanced stages.
Received: 24 November 1999 / Accepted: 21 April 2000 相似文献
100.
Michael G Kiehl Ludwig Kraut Rainer Schwerdtfeger Bernd Hertenstein Mats Remberger Nicolaus Kroeger Mathias Stelljes Martin Bornhaeuser Hans Martin Christoph Scheid Arnold Ganser Axel R Zander Joachim Kienast Gerhard Ehninger Dieter Hoelzer Volker Diehl Axel A Fauser Olle Ringden 《Journal of clinical oncology》2004,22(14):2816-2825
PURPOSE: The role of unrelated allogeneic stem-cell transplantation in acute lymphoblastic leukemia (ALL) patients is still not clear, and only limited data are available from the literature. We analyzed factors affecting clinical outcome of ALL patients receiving a related or unrelated stem-cell graft from matched donors. PATIENTS AND METHODS: The total study population was 264 adult patients receiving a myeloablative allogeneic stem-cell transplant for ALL at nine bone marrow transplantation centers between 1990 and 2002. Of these, 221 patients receiving a matched related or unrelated graft were analyzed. One hundred forty-eight patients received transplantation in complete remission; 62 patients were in relapse; and 11 patients were refractory to chemotherapy before transplant. Fifty percent of patients received bone marrow, and 50% received peripheral blood stem cell from a human leukocyte antigen-identical related (n = 103), or matched unrelated (n = 118) donor. RESULTS: Disease-free survival (DFS) at 5 years was 28%, with 76 patients (34%) still alive (2.2 to 103 months post-transplantation), and 145 deceased (65 relapses, transplant-related mortality, 45%). We observed an advantage regarding DFS in favor of patients receiving transplantation during their first complete remission (CR) in comparison with patients receiving transplantation in or after second CR (P =.014) or who relapsed (P <.001). We observed a clear trend toward improved survival in favor of B-lineage ALL patients compared with T-lineage ALL patients (P =.052), and Philadelphia chromosome-positive patients had no poorer outcome than Philadelphia chromosome-negative patients. Total-body irradiation-based conditioning improved DFS in comparison with busulfan (P =.041). CONCLUSION: Myeloablative matched related or matched unrelated allogeneic hematopoietic stem-cell transplantation in ALL patients should be performed in first CR. 相似文献