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Gurr E.,Abteilung fur Klinische Chemie | Arzideh F.,University of Bremen | Brandhorst G.,Universitatsklinikum | Groning A.,MVZ Wagnerstibbe | And 6 more authors.
LaboratoriumsMedizin | Year: 2011

Following DIN EN ISO 15189 and the Richtlinien der Bundesärztekammer zur Qualiẗtssicherung laboratoriumsmedizinischer Untersuchungen pre-examination procedures have to be established in order to make results as comparable as possible. For standardization of the pre-examination variables the working group "Richtwerte" (guide values) of the DGKL proposes an exemplary standard operation procedure adjustable to local environments. Using the proposed standard operation procedure the estimation of reference intervals should lead to more valid and comparable results. © 2011 by Walter de Gruyter.


Seelig H.P.,Medizinisches Versorgungszentrum Labor Prof Seelig | Appelhans H.,Medizinisches Versorgungszentrum Labor Prof Seelig | Bauer O.,Medizinisches Versorgungszentrum Labor Prof Seelig | Bluthner M.,Medizinisches Versorgungszentrum Labor Prof Seelig | And 5 more authors.
Clinical Laboratory | Year: 2011

Background: Indirect immunofluorescence (HFT) on in house HEp-2 cell preparations revealed a novel antibody giving a granular cytoplasmic pattern not described before, which on two commercial cell preparations revealed a "rings and rods" pattern. This pattern was also observed in four HCV-RNA carriers and prompted the identification of the reactive antigen and the evaluation of the antibody prevalence in HCV-RNA carriers and control groups. Methods: The antigen's molecular weight was determined by radioimmunoprecipitation of 35S-methionine labeled cell proteins. Expression library screening and sequencing was performed by standard techniques using an oligo(dT)-primed human HeLa cell cDNA expression library. Antibodies against the novel antigen Inositol-5′-monophosphatdehydrogenase 2 (IMPDH2) were analyzed by HFT, western blot, line blot, and radioimmunoprecipitation assay (RIPA). HFT was performed on commercial HEp-2 cells and cells cultivated in house for 24-60 hours, with or without the IMPDH2 inhibitors mycophenolic acid (MPA) or ribavirin, and subjected to various fixation conditions. Western and line blots were performed with IMPDH2 synthesized in E. coli, RIPA with 35S-methionine-IMPDH2 from in vitro transcription/translation products. Sera screened were positive for HCV-RNA (108), HBV-DNA (100), anti-mitochondrial (31), anti-actin (42), and anti-nuclear antibodies (51) and negative for HCV-RNA (100) and blood donors (100). Results: IMPDH2 is capable of considerable intracellular rearrangements (upon action of inhibitors like MPA and ribavirin), which explains the contrasting immunofluorescence patterns in cells from different sources. By RIPA, proven to be the sole assay suitable for screening of anti-IMPDH2 in human sera, autoantibodies were found in 35.2% of HCV-RNA carriers and in low concentrations in 31% of anti-actin positive patients suspicious of autoimmune hepatitis. Antibodies reacted preferentially with conformational epitopes. Compared to the low concentration of anti-IMPDH2 found in other disease groups, high antibody concentrations were observed in HCV-RNA carriers. Conclusions: The common occurrence of anti-IMPDH2 in HCV-RNA carriers may be related to ribavirin therapy, causing intracellular aggregation of IMPDH2 thereby altering its immunogenicity. In this study the "rods and rings" immunofluorescence pattern observed could be ascribed to anti-IMPDH2. Anti-IMPDH2 may cause difficulties in interpretation of immunofluorescence patterns in routine autoantibody testing.


Vollmer T.,Institute For Laboratoriums Und Transfusionsmedizin | Hinse D.,Institute For Laboratoriums Und Transfusionsmedizin | Kleesiek K.,Institute For Laboratoriums Und Transfusionsmedizin | Dreier J.,Institute For Laboratoriums Und Transfusionsmedizin
BMC Microbiology | Year: 2010

Background: Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental in vitro IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 Streptococcus gallolyticus subsp. gallolyticus strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms in vitro was examined in order to reveal features of S. gallolyticus subsp. gallolyticus endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors gtf, pilB, and fimB by PCR. Results. The adherence to and invasion characteristics of the examined S. gallolyticus subsp. gallolyticus strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different in vitro models (EA.hy926 cells, primary endothelial cells (HUVECs), mechanical stretched cells) revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (fimB: all strains, gtf: 19 of 23 strains) and demonstrated the presence of the gene of one new putative virulence factor (pilB: 9 of 23 strains) by PCR. Conclusion. Our study provides the first description of S. gallolyticus subsp. gallolyticus adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen. © 2010 Vollmer et al; licensee BioMed Central Ltd.


Vollmer T.,Institute For Laboratoriums Und Transfusionsmedizin | Kleesiek K.,Institute For Laboratoriums Und Transfusionsmedizin | Dreier J.,Institute For Laboratoriums Und Transfusionsmedizin
Methods in Molecular Biology | Year: 2013

Despite considerable advances in the safety of blood components based on the application of highly sensitive and specific screening methods to minimize the viral infection risk, the prevention of transfusion-associated bacterial infection remains a major challenge in transfusion medicine. In particular, platelet concentrates represent the greatest infectious risk of transfusion-transmitted bacterial sepsis. The detection of bacterial contamination in platelet concentrates has been implemented in several blood services as a routine quality control testing. Although culture is likely to remain the gold standard method of detecting bacterial contamination, the use of rapid methods is likely to increase and play an important role in transfusion medicine in the future. In particular, flow cytometric methods and nucleic acid amplification techniques are powerful tools in bacterial screening assays. Compared to culture-based methods, the combination of high sensitivity and specificity, low contamination risk, ease of performance, and speed has made those technologies appealing alternatives to conventional culture-based testing methods. © 2013 Springer Science+Business Media, LLC.


Wolters B.,Institute For Laboratoriums Und Transfusionsmedizin | Zander G.,IMP Computersysteme AG OSM Gruppe | Blasius P.,SWISSLAB GmbH
LaboratoriumsMedizin | Year: 2010

Accounting services of a medical laboratory are important for an organisation to be profitable. Increasingly complex structures of an organisation need to be considered. Many medical laboratories use laboratory information systems (LISs) that have to support accounting. Here, we describe the current state of accounting in medical laboratories. We focus on special situations in laboratory medicine and on relevant differences between accounting with LISs and accounting with third party or patient administration systems. Accounting with a patient administration system seems to be the simplest method, but special circumstances need to be considered. The more complex the requesting structure is, the more accounting with LISs is recommended. A checklist will provide the reader with the opportunity to choose a matching method of accounting for each individual situation of the laboratory in question. In particular, the "Kassenärztliche Vereinigungen", responsible for accounting with compulsory health insurances, is currently undergoing large-scale changes. In the near future more changes are to be expected, particularly with the new medical fee regulation. © 2010 by Walter de Gruyter Berlin New York 2010.


PubMed | Institute For Laboratoriums Und Transfusionsmedizin
Type: | Journal: BMC microbiology | Year: 2010

Streptococcus gallolyticus subsp. gallolyticus is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental in vitro IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 Streptococcus gallolyticus subsp. gallolyticus strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms in vitro was examined in order to reveal features of S. gallolyticus subsp. gallolyticus endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors gtf, pilB, and fimB by PCR.The adherence to and invasion characteristics of the examined S. gallolyticus subsp. gallolyticus strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different in vitro models (EA.hy926 cells, primary endothelial cells (HUVECs), mechanical stretched cells) revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (fimB: all strains, gtf: 19 of 23 strains) and demonstrated the presence of the gene of one new putative virulence factor (pilB: 9 of 23 strains) by PCR.Our study provides the first description of S. gallolyticus subsp. gallolyticus adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen.


PubMed | Institute For Laboratoriums Und Transfusionsmedizin
Type: | Journal: Methods in molecular biology (Clifton, N.J.) | Year: 2012

Despite considerable advances in the safety of blood components based on the application of highly sensitive and specific screening methods to minimize the viral infection risk, the prevention of transfusion-associated bacterial infection remains a major challenge in transfusion medicine. In particular, platelet concentrates represent the greatest infectious risk of transfusion-transmitted bacterial sepsis. The detection of bacterial contamination in platelet concentrates has been implemented in several blood services as a routine quality control testing. Although culture is likely to remain the gold standard method of detecting bacterial contamination, the use of rapid methods is likely to increase and play an important role in transfusion medicine in the future. In particular, flow cytometric methods and nucleic acid amplification techniques are powerful tools in bacterial screening assays. Compared to culture-based methods, the combination of high sensitivity and specificity, low contamination risk, ease of performance, and speed has made those technologies appealing alternatives to conventional culture-based testing methods.

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