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Dive into the research topics where Georg Wittmann is active.

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Featured researches published by Georg Wittmann.


PLOS ONE | 2014

The Role of Therapeutic Leukapheresis in Hyperleukocytotic AML

Friederike Pastore; Alessandro Pastore; Georg Wittmann; Wolfgang Hiddemann; Karsten Spiekermann

Purpose Hyperleukocytosis in AML with leukostasis is a serious life-threatening condition leading to a high early mortality which requires immediate cytoreductive therapy. Therapeutic leukapheresis is currently recommended by the American Society of Apheresis in patients with a WBC>100 G/l with signs of leukostasis, but the role of prophylactic leukapheresis before clinical signs of leukostasis occur is unclear. Patients We retrospectively analyzed the role of leukapheresis in 52 patients (median age 60 years) with hyperleukocytotic AML with and without clinical signs of leukostasis. Since leukapheresis was performed more frequently in patients with signs of leukostasis due to the therapeutic policy in our hospital, we developed a risk score for early death within seven days after start of therapy (EDd7) to account for this selection bias and to independently measure the effect of leukapheresis on EDd7. Results 20 patients received leukapheresis in combination to chemotherapy compared to 32 patients who received chemotherapy only. In a multivariate logistic regression model for the estimation of the probability of EDd7 thromboplastin time and creatinine remained as independent significant parameters and were combined to create an EDd7 risk score. The effect of leukapheresis on EDd7 was evaluated in a bivariate logistic regression together with the risk score. Leukapheresis did not significantly change early mortality in all patients with a WBC≥100 G/l. Discussion Prophylactic leukapheresis in hyperleukocytotic patients with and without leukostasis did not improve early mortality in our retrospective study. Larger and prospective clinical trials are needed to validate the risk score and to further explore the role of leukapheresis in AML with hyperleukocytosis.


Cell | 2017

The DNA Inflammasome in Human Myeloid Cells Is Initiated by a STING-Cell Death Program Upstream of NLRP3

Moritz M. Gaidt; Thomas S. Ebert; Dhruv Chauhan; Katharina Ramshorn; Francesca Pinci; Sarah Zuber; Fionán Ó Dúill; Jonathan L. Schmid-Burgk; Florian Hoss; Raymund Buhmann; Georg Wittmann; Eicke Latz; Marion Subklewe; Veit Hornung

Detection of cytosolic DNA constitutes a central event in the context of numerous infectious and sterile inflammatory conditions. Recent studies have uncovered a bipartite mode of cytosolic DNA recognition, in which the cGAS-STING axis triggers antiviral immunity, whereas AIM2 triggers inflammasome activation. Here, we show that AIM2 is dispensable for DNA-mediated inflammasome activation in human myeloid cells. Instead, detection of cytosolic DNA by the cGAS-STING axis induces a cell death program initiating potassium efflux upstream of NLRP3. Forward genetics identified regulators of lysosomal trafficking to modulate this cell death program, and subsequent studies revealed that activated STING traffics to the lysosome, where it triggers membrane permeabilization and thus lysosomal cell death (LCD). Importantly, the cGAS-STING-NLRP3 pathway constitutes the default inflammasome response during viral and bacterial infections in human myeloid cells. We conclude that targeting the cGAS-STING-LCD-NLRP3 pathway will ameliorate pathology in inflammatory conditions that are associated with cytosolic DNA sensing.


Transfusion Medicine and Hemotherapy | 2007

Automation and Data Processing with the Immucor Galileo ® System in a University Blood Bank

Georg Wittmann; Josef Frank; Wolfgang Schramm; Michael Spannagl

The implementation of automated techniques improves the workflow and quality of immunohematological results. The workflows of our university blood bank were reviewed during the implementation of an automated immunohematological testing system. Methods: Work impact of blood grouping and subgrouping, cross-matching and antibody search using the Immucor Galileo system was compared to the previous used standard manual and semi-automated methods. Results: The redesign of our workflow did not achieve a significant reduction of the specimen’s working process time, the operator’s time however was reduced by 23%. Corresponding results were achieved for blood grouping, Rhesus typing, antibody screen and for autocontrol when changing from two semi-automated to the Galileo system. Because of the higher sensitivity of the Immucor antibody detection system, the rate of the initial positive antibody screens rose from 4 to 6% Conclusion: The Immucor Galileo system automates routine blood bank testing with high reliability, specificity and higher sensitivity compared to our previous used standard manual and semi-automated methods.


Transplant International | 2005

Successful ABO-incompatible heart transplantation in two infants

Michael Schmoeckel; Sabine Däbritz; Rainer Kozlik-Feldmann; Georg Wittmann; Frank Christ; Christian Kowalski; Bruno Meiser; Heinrich Netz; Bruno Reichart

In the pediatric age group shortage of donor hearts leads to mortality rates of 30–50% on the waiting list. Because of the immaturity of the immune system of infants, ABO‐incompatible heart transplantation may be an option to increase donor availability. We transplanted two infants with blood type O at the age of 7 and 5 months, respectively, with complex congenital heart disease. Intraoperative plasma exchange was performed during cardiopulmonary bypass followed by standard immunosuppression. Both recipients received a blood type A donor organ. Plasma was exchanged up to six times until anti‐A antibodies were eliminated. No hyperacute rejection occurred, ventricular function is excellent and there have been no acute rejection episodes up to 4 months after transplantation. Anti‐A antibody titers remained low and eventually disappeared. ABO‐incompatible cardiac transplantation shows good short‐term results in young infants and appears to be a safe procedure to reduce mortality on the waiting list.


Scandinavian Journal of Urology and Nephrology | 2017

Dramatic impact of blood transfusion on cancer-specific survival after radical cystectomy irrespective of tumor stage

Alexander Buchner; Tobias Grimm; Birte-Swantje Schneevoigt; Georg Wittmann; Alexander Kretschmer; Friedrich Jokisch; Markus Grabbert; Maria Apfelbeck; Gerald Schulz; Christian Gratzke; Christian G. Stief; Alexander Karl

Abstract Objective: The aim of the present study was to determine the influence of intraoperative and postoperative blood transfusion on cancer-specific outcome. Materials and methods: Follow-up data were collected from 722 patients undergoing radical cystectomy for urothelial carcinoma of the bladder (UCB) between 2004 and 2014. Median follow-up was 26 months (interquartile range 12–61 months). Outcome was analyzed in relation to the amount of intraoperative and postoperative blood transfusion and different tumor stages. The primary endpoint was cancer-specific survival (CSS) after cystectomy. Kaplan–Meier analysis with log-rank test and Cox regression models were used. Results: Intraoperative blood transfusion was given in 36% (263/722) and postoperative blood transfusion in 18% (132/722). In patients with and without intraoperative blood transfusion, 5 year CSS was 48% and 67%, respectively (p < .001). In patients with and without postoperative blood transfusion, 5 year CSS was 48% and 63%, respectively (p < .001). The number of transfused red blood cell (RBC) units [intraoperatively: hazard ratio (HR) = 1.08, 95% confidence interval (CI) 1.01–1.15, p = .023; postoperatively: HR = 1.14, 95% CI 1.07–1.21, p < .001] was an independent prognostic factor for CSS. The dose-dependent negative effect of transfusions was also found in favorable subgroups (pT1 tumor, hemoglobin ≥13 mg/dl, p = .004) and in a high-volume surgeon subgroup (n = 244, p < .001). Conclusions: Blood transfusions during and after radical cystectomy were independent prognostic factors for CSS in this retrospective study. Therefore, efforts should be made to reduce the necessity of intraoperative and postoperative blood transfusion in cystectomy patients.


Thrombosis and Haemostasis | 2008

Successful salvage treatment of chronic refractory immune thrombocytopenia using a simplified method to generate vincristine-loaded platelets

Oliver Weigert; Georg Wittmann; Stefanie Gruetzner; Jitske Cnossen; Marie-Christine Becker; Martin Dreyling; Helmut Ostermann

Successful salvage treatment of chronic refractory immune thrombocytopenia using a simplified method to generate vincristine-loaded platelets -


Cell and Tissue Banking | 2010

Eurocode International Blood Labeling System enables unique identification of all biological products from human origin in accordance with the European Directive 2004/23/EC

Ralf Knels; Hans-Joachim Mönig; Georg Wittmann; Rüdiger von Versen; Axel Pruss

Due to their limited availability and compatibility, biological products must be exchanged between medical institutions. In addition to a number of national systems and agreements which strive to implement a unique identification and classification of blood products, the ISBT 128 was developed in 1994, followed by the Eurocode in 1998. In contrast to other coding systems, these both make use of primary identifiers as stipulated by the document ISO/IEC 15418 of the International Organization for Standardization (ISO), and thus provide a unique international code. Due to their flexible data structures, which make use of secondary identifiers, both systems are able to integrate additional biological products and their producers. Tissue and cells also constitute a comparable risk to the recipient as that of blood products in terms of false labeling and the danger of infection. However, in contrast to blood products, the exchange of tissue and cells is much more intensively pursued at the international level. This fact is recognised by Directives 2004/23/EC and 2006/86/EC of the European Union (EU), which demand a standardized coding system for cells and tissue throughout the EU. The 2008 workshop agreement of the European Committee for Standardization (CEN) was unique identification by means of a Key Code consisting of country code corresponding to ISO 3166-1, as well as competent authority and tissue establishment. As agreed at the meeting of the Working Group on the European Coding System for Human Tissues and Cells of the Health and Consumers Directorate-General of the European Commission (DG SANCO) held on 19 May 2010 in Brussels, this Key Code could also be used with existing coding systems to provide unique identification and allow EU traceability of all materials from one donation event. Today Eurocode already uses country codes according to ISO 3166-1, and thus the proposed Key Code can be integrated into the current Eurocode data structure and does not need to be introduced separately. The Eurocode product classification for all products is based on its own unique coding system, which can be accessed over the internet by all users who are not themselves members of Eurocode. In summary, it can be said that the standardized single coding system for tissues and cells requires only unique sections in the data structure such the Key Code to fulfil the requirements of the EU Directive. Thus, various systems currently in place in different EU member states can continue to operate if the Key Code as suggested by the EU is integrated into them. The classification and description of each product characteristic is currently being discussed by the DG SANCO Working Group on the European Coding System for Human Tissues and Cells. Following intensive scrutiny in light of the stipulations laid out in EU Directives 2004/23/EC and 2006/86/EC as well as the CEN/ISSS workshop agreements, the Germany Federal Ministry for Health and organisations representing German tissue establishments under the responsibility of the German Society of Transfusion Medicine and Immunohematology, Working Party “Tissue preparations” proposed in 2009 that Eurocode be adopted for the donor identification and product coding of tissue and cells in Germany. The technical details for implementation have already been completed and are presented in the current article.


Transfusion Medicine and Hemotherapy | 2016

Blood Product Supply in Germany: The Impact of Apheresis and Pooled Platelet Concentrates

Karin Berger; Dorothee Schopohl; Georg Wittmann; Wolfgang Schramm; Helmut Ostermann; Christina Rieger

Background: In Germany, about 60% of all produced platelet concentrates (PCs) are apheresis PCs (APCs). Ongoing discussions on APC reimbursement and costs might lead to a potential shift in pooled PC (PPC)/APC production. Objective of this analysis was to build a comprehensive model from the societal perspective to evaluate consequences associated with shifts in platelet supply and demand. Methods: Literature search, desktop researches on platelet supply and demand. Model calculations, time horizon one year: model input from the Paul-Ehrlich-Institute, data 2013. Base case: 19.2% of annual whole blood donations (WBDs) were used for production of 38.5% PPCs, decay of 46,218 PCs (8.0%). Scenarios calculated: variation in PPC proportion of 10-100%. Results: Base case: during PPC production 41,957-83,913 red blood cell concentrates (RBCCs) are estimated to be lost, which corresponds to 1-2% of annual RBCCs in Germany. Scenarios were calculated for a production of 60-100% PPCs: loss is estimated to be 1.5-5.0% of annual RBCCs (65,430-218,099), decay 54,189-69,022 PCs (9.4-12.0%). Conclusion: Production of different blood components is interlinked and sensitive to unidimensional decisions. Increasing PPC proportion has negative impact on the RBCC production and on the antigen-matched APC donor pool. Completion of the model calculations to predict the optimal PPC/APC proportion would require evidence on the number of refractory patients, donor pool sizes, and incidences of diseases requiring platelet transfusions.


Transfusion Medicine and Hemotherapy | 2008

Contents of Forthcoming Issues · Themenvorschau

Axel Pruss; Jan Claas Brune; Ralf Knels; Hans-Joachim Mönig; Georg Wittmann; Rüdiger von Versen; Thomas Meyer; Susanne Polywka; Birgit Wulff; Carolin Edler; Ann Sophie Schröder; Ina Wilkemeyer; Ulrich Kalus; Jan Schroeter; Reinhold A. Schiller; Frithjof Herrlinger; Katja Müller; Axel Heinemann; Klaus Püschel; Uwe Hesselbarth; Philipp Seifert; Dimitri Nowack; Mark David Smith; Dirk Seifert; Knut Gubbe; Yvonne Scharnagl; Steffi Grosch; Torsten Tonn; Michael F.G. Schmidt; Kai M. Hourfar

Spinal cord chimeras were produced by replacing a small fragment of neural tube of a 2-day-old White Leghorn chicken embryo with a similar fragment from a Japanese quail embryo. The embryo mortality was 61%, and 72% of hatched birds were ‘cripples’ and had to be sacrificed within 5 days after hatching. Forty-nine chimeras, 10.9% of the total number of operated embryos, were alive for more than 3 weeks. For at least 17 days after hatching, all birds behaved like normal chicks, and the grey quail-like feathers were the only manifestations of their chimerism. Initial neurological symptoms of unsteady walking and drooping of the wings were noted in all birds except for 1 that died an accidental death before it became sick. Advanced symptoms characterized by paralysis of the legs forcing the bird to lie on its side were noted in 40 birds. The chimeras could be divided into two groups, each consisting of 24 birds. The short-survival (SS) chimeras of the first group became terminally ill and had to be sacrificed within 3 months. The long-survival (LS) chimeras of the second group showed more protracted disease, in that only 16 of them showed symptoms of the advanced disease, and the majority showed partial or complete recovery. Ten of the LS birds were kept alive for more than 8 months. Furthermore, many LS chimeras lost their grey feathers. The hallmarks of neurohistological manifestations were mononuclear cell infiltrates, demyelinization with preservation of axons and scar formation. These lesions were restricted to the quail fragment of the spinal cord except for 2 birds in which distant cellular infiltrates were observed. Direct immunofluorescence tests for chicken IgG were positive in spinal cords of most SS chimeras but only of some LS chimeras.


European Journal of Cardio-Thoracic Surgery | 2007

Blood type incompatible cardiac transplantation in young infants

Sabine Daebritz; Michael Schmoeckel; Helmut Mair; Rainer Kozlik-Feldmann; Georg Wittmann; Christian Kowalski; Ingo Kaczmarek; Bruno Reichart

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Axel Pruss

Humboldt University of Berlin

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Kai M. Hourfar

Goethe University Frankfurt

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