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41.
The eicosapentaenoic to docosahexaenoic acid ratio of diets affects the pathogenesis of arthritis in Lew/SSN rats 总被引:6,自引:0,他引:6
Dietary-induced changes in tissue levels of polyunsaturated fatty acids modify inflammatory reactions through changes in the synthesis of lipid and peptide mediators of inflammation. Four semipurified 20% fat diets, based on beef tallow (BT), safflower oil (SFO), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were provided. The DHA and EPA ratios of the (n-3) fatty acid-based diets were 1.1 and 3.4, respectively. The effect of prefeeding diets differing in EPA to DHA ratios prior to the induction of streptococcal cell wall (SCW) arthritis in female Lew/SSN rats was examined. Weanling rats were fed diets for 5 wk before arthritis induction and 5 wk post-arthritis induction. Footpad thickness, hock circumference, plasma and macrophage fatty acids and histological assessment were compared. There were no differences in food intake and final body weights among the groups. Footpad inflammation, reported as percentage change (adjusted for growth) was greatest for rats fed the BT-based diet, intermediate in those fed the SFO-based diet and least for the rats fed the EPA- and DHA-based diets (P < 0.05). Macrophage phospholipids revealed cellular incorporation of EPA and DHA from the fish-oil based diets which modified lipid and peptide mediators of inflammation. Histological sections of rat hocks ranked by severity of arthritis-related changes suggested that the SFO- and EPA-based diets were more successful in ameliorating the destructive arthritic phase in hock joints than the BT- and DHA-based diets (P = 0.09) in this model of arthritis. The course of SCW-induced arthritis can be altered by diet-induced changes in macrophage fatty acid composition. The EPA-based diet is more effective in suppression of inflammation than the DHA-based diet. 相似文献
42.
Sonja Loges Gerhard Heil Melanie Bruweleit Volker Schoder Martin Butzal Uta Fischer Ursula M Gehling Gunter Schuch Dieter K Hossfeld Walter Fiedler 《Journal of clinical oncology》2005,23(6):1109-1117
PURPOSE: Bone marrow neoangiogenesis plays an important pathogenetic and possible prognostic role in acute myeloid leukemia (AML). Members of the vascular endothelial growth factor (VEGF) and angiopoietin family represent the most specific inducers of angiogenesis secreted by AML blasts. We therefore correlated expression of angiogenic factors with clinical variables. PATIENTS AND METHODS: We investigated the expression of VEGF-A, VEGF-C, angiopoietin-1 (Ang1), angiopoietin-2 (Ang2), and the receptor Tie2 by quantitative polymerase chain reaction in a cohort of 90 patients younger than 61 years with de novo AML entered into the German AML Süddeutsche H?moblastose Gruppe Hannover 95 trial. Uni- and multivariate analyses were performed using clinical and gene expression variables. RESULTS: Univariate analysis of overall survival indicated the following variables as prognostic factors: good response on a day-15 bone marrow examination after initiation of induction chemotherapy, karyotype, and high Ang2 expression. In multivariate analysis, only bad response and log Ang2 expression remained of statistical significance, with a hazard ratio of 3.51 (95% CI, 1.91 to 6.47) and 0.75 (95% CI, 0.61 to 0.91), respectively. Subgroup analysis suggested that the prognostic impact of Ang2 expression was especially evident in cohorts with low VEGF-C and Ang1 mRNA levels. CONCLUSION: These results show that expression of Ang2 represents an independent prognostic factor in AML. Additional research into interactions of angiogenic cytokines in the pathogenesis of bone marrow angiogenesis in AML is warranted. 相似文献
43.
Roland Schnell Markus Dietlein Jan Oliver Staak Peter Borchmann Klaus Schomaecker Thomas Fischer Wolfgang Eschner Hinrich Hansen Franck Morschhauser Harald Schicha Volker Diehl Andrew Raubitschek Andreas Engert 《Journal of clinical oncology》2005,23(21):4669-4678
PURPOSE: Hodgkin's lymphoma (HL) has been demonstrated to be a good target for immunotherapy since lymphocyte activation markers such as CD30 are expressed in high numbers on the malignant cells. Thus, we developed a new radioimmunoconjugate consisting of the murine anti-CD30 monoclonal antibody (MAb) Ki-4 labeled with iodine-131 ((131)I). PATIENTS AND METHODS: The biodistribution of (131)I-Ki-4 was assessed via dosimetry after preinfusion of 5 mg native Ki-4 followed by 250 to 300 MBq (131)I-labeled Ki-4. Whole-body scintigraphy was performed 1 hour, 24 hours, 48 hours, 72 hours, and 6 days after the infusion. Dosimetry was calculated using the programs NucliDose ICON-IDL (version 5.0.2; Siemens, Erlanger, Germany) and MIRDOSE (version 3.1; Oak Ridge National Laboratories; Oak Ridge, TN). The therapeutic dose was given on day 8 after preinfusion of unlabeled Ki-4. RESULTS: We treated 22 patients with relapsed or refractory CD30-positive HL. Preinfusion of 5 mg native Ki-4 was sufficient to bind the soluble CD30. Imaging demonstrated localization of involved areas measuring 5 cm in diameter or more in four patients and 2.5 cm in one patient. Patients received total body doses of 0.035 Gy to 0.99 Gy. Acute toxicity was mild with grade 1 fatigue in 19 of 22 assessable patients. Seven patients experienced grade 4 degrees hematotoxicity 4 to 8 weeks after treatment. Response included one complete remission, five partial remissions, and three minor responses. CONCLUSION: Treatment with (131)I-Ki-4 is effective but can be associated with severe hematotoxicity. 相似文献
44.
Maren Hedtke Rodrigo Pessoa Rejas Matthias F. Froelich Volker Ast Angelika Duda Laura Mirbach Victor Costina Uwe M. Martens RalfDieter Hofheinz Michael Neumaier Verena Haselmann 《Molecular oncology》2022,16(10):2042
The analysis of circulating tumor DNA (ctDNA) is at the threshold of implementation into standard care for colorectal cancer (CRC) patients. However, data about the clinical utility of liquid profiling (LP), its acceptance by clinicians, and its integration into clinical workflows in real‐world settings remain limited. Here, LP tests requested as part of routine care since 2016 were retrospectively evaluated. Results show restrained request behavior that improved moderately over time, as well as reliable diagnostic performance comparable to translational studies, with an overall agreement of 91.7%. Extremely low ctDNA levels at < 0.1% in over 20% of cases, a high frequency of concomitant driver mutations (in up to 14% of cases), and ctDNA levels reflecting the clinical course of disease were revealed. However, certain limitations hampering successful translation of ctDNA into clinical practice were uncovered, including the lack of clinically relevant ctDNA thresholds, appropriate time points of LP requests, and integrative evaluation of ctDNA, imaging, and clinical findings. In conclusion, these results highlight the potential clinical value of LP for CRC patient management and demonstrate issues that need to be addressed for successful long‐term implementation in clinical workflows. 相似文献
45.
Harald Treuer Martin Kocher Moritz Hoevels Stefan Hunsche Klaus Luyken Mohammad Maarouf Jürgen Voges Rolf-Peter Müller Volker Sturm 《Radiotherapy and oncology》2006,81(1):25-32
OBJECTIVE: Determination of the impact of inaccuracies in the determination and setup of the target point in stereotactic radiosurgery (SRS) on the expectable complication and control probabilities. METHODS: Two randomized samples of patients with arteriovenous malformation (AVM) (n=20) and with brain metastases (n=20) treated with SRS were formed, and the probability for complete obliteration (COP) or complete remission (CRP), the size of the 10 Gy-volume in the brain tissue (VOI10), and the probability for radiation necrosis (NTCP) were calculated. The dose-effect relations for COP and CRP were fitted to clinical data. Target point deviations were simulated through random vectors and the resulting probabilities and volumes were calculated and compared with the values of the treatment plan. RESULTS: The decrease of the relative value of the control probabilities at 1mm target point deviation was up to 4% for AVMs and up to 10% for metastases. At 2 mm the median decrease was 5% for AVMs and 9% for metastases. The value for the target point deviation, at which COP and CRP decreased about 0.05 in 90% of the cases, was 1.3 mm. The increase of NTCP was maximally 0.0025 per mm target point deviation for AVMs and 0.0035/mm for metastases. The maximal increase of VOI10 was 0.7 cm(3)/mm target point deviation in both patient groups. CONCLUSIONS: The upper limit for tolerable target point deviations is at 1.3mm. If this value cannot be achieved during the system test, a supplementary safety margin should be applied for the definition of the target volume. A better accuracy level is desirable, in order to ensure optimal chances for the success of the treatment. The target point precision is less important for the minimization of the probability of radiation necroses. 相似文献
46.
Abstract Weight gain during pregnancy is of great importance for the health of mother and child. There is considerable individual variability with regard to the weight gain, with maternal height and pre-pregnancy body weight being important determinants. We aim to assess the usefulness of the maternal body mass index (BMI) and other ways of combining maternal weight and height in predicting weight gain during pregnancy. We analyzed data of more than 2.2 million pregnancies taken from the German perinatal statistics of 1995-2000. We found that BMI is not useful as a predictor of weight gain during pregnancy. We developed an alternative system of using maternal weight and height to predict weight gain by classifying pregnant women according to their weight and height. This allows an assessment of weight gain by comparing a given pregnant woman to other women with similar weights and heights. 相似文献
47.
Sylvia J. Gasparini Karen Tessmer Miriam Reh Stephanie Wieneke Madalena Carido Manuela Vlkner Oliver Borsch Anka Swiersy Marta Zuzic Olivier Goureau Thomas Kurth Volker Busskamp Günther Zeck Mike O. Karl Marius Ader 《The Journal of clinical investigation》2022,132(12)
Once human photoreceptors die, they do not regenerate, thus, photoreceptor transplantation has emerged as a potential treatment approach for blinding diseases. Improvements in transplant organization, donor cell maturation, and synaptic connectivity to the host will be critical in advancing this technology for use in clinical practice. Unlike the unstructured grafts of prior cell-suspension transplantations into end-stage degeneration models, we describe the extensive incorporation of induced pluripotent stem cell (iPSC) retinal organoid–derived human photoreceptors into mice with cone dysfunction. This incorporative phenotype was validated in both cone-only as well as pan-photoreceptor transplantations. Rather than forming a glial barrier, Müller cells extended throughout the graft, even forming a series of adherens junctions between mouse and human cells, reminiscent of an outer limiting membrane. Donor-host interaction appeared to promote polarization as well as the development of morphological features critical for light detection, namely the formation of inner and well-stacked outer segments oriented toward the retinal pigment epithelium. Putative synapse formation and graft function were evident at both structural and electrophysiological levels. Overall, these results show that human photoreceptors interacted readily with a partially degenerated retina. Moreover, incorporation into the host retina appeared to be beneficial to graft maturation, polarization, and function. 相似文献
48.
Henrik Fox Takayuki Gyoten Sebastian V Rojas Volker Lauenroth Sabina Günther Ren Schramm Jan F Gummert Michiel Morshuis 《Interactive Cardiovascular and Thoracic Surgery》2022,35(1)
Open in a separate window OBJECTIVESPump thrombosis remains a major challenge in heart failure patients with left ventricular HeartWare assist device. Current International Society for Heart and Lung Transplantation recommendations favour surgical pump exchange over lysis because safety and efficacy of lysis has been controversially reported. This study summarizes our experience on our HeartWare thrombosis prevention strategy as well as thrombolysis through implementation of our institutional standardized HeartWare assist device protocol.METHODSOutcomes of all HeartWare thrombosis patients admitted between 2010 and 2020 were analysed. Thrombolysis therapy using tissue plasminogen activator was used as the first-line therapy in this study and thrombolysis therapy efficacy was defined as freedom from stroke, bleeding, recurrent HeartWare assist device thrombosis or surgical device exchange within 30 days after lysis application.RESULTSA total of 507 patients have been included in this study and 66 patients (13%) collectively developed a first HeartWare-thrombosis after a median of 12 months (8–22 months) after HeartWare implantation. Forty patients were treated with unstandardized lysis, of whom 7 patients had thrombolysis associated complications, such as incomplete thrombus resolution requiring surgical pump exchange in 4 patients, but also intracranial haemorrhage occurring in 3 patients. Three patients died in the non-protocol group. Eight device thrombosis patients were treated according to our protocol, showing no lysis-associated complication.CONCLUSIONSDespite current recommendations, preferring surgical HeartWare pump exchange in thrombosis, thrombolysis therapy for first HeartWare thrombosis can be safe and effective in a standardized protocol setting, including anticoagulation adjustment and intensified blood pressure control management. 相似文献
49.
In the classical theory of thermoelectricity, the performance integrals for a fully self-compatible material depend on the dimensionless figure of merit zT. Usually these integrals are evaluated for constraints z = const. and zT = const., respectively. In this paper we discuss the question from a mathematical point of view whether there is an optimal temperature characteristics of the figure of merit. We solve this isoperimetric variational problem for the best envelope of a family of curves z(T)T. 相似文献
50.
The development of vaccines for infants and young children requires the use of animal models at various stages of preclinical development. Animal models are being used to assess the quantity and quality of the immune response, onset and duration of the response, induction of systemic versus local immunity, protection against challenge infection for the assessment of vaccine efficacy, as well as safety and toxicity of the vaccine formulation itself. A variety of animal models are available, each with its own specific advantages and disadvantages. Here, we review the most common animal models for preclinical vaccine development for human infants. 相似文献