Bayer Diagnostics

Dipstick tests designed to assess microalbuminuria in humans (Clinitek Microalbumin Test, Bayer Diagnostics Corporation) are not accurate for use in animals (Pressler et al. 2002). Dipsticks for point-intime assessment of microalbuminuria in dogs and cats are commercially available (Heska Corporation). 

The theory of Kubelka and Munk is used in calculating the concentration for the systems of Boehringer Mannheim, Hoffmann-La Roche and Bayer Diagnostic and Electronic (Ames-Miles). If modifications of the theory have been made, these are stated in the description of the instrument. If the relationship between reflection and concentration (calculated by means of the theory of Kubelka and Munk) is represented graphically, the curve obtained is similar to that for the relationship between transmission and concentration calculated by Beer-Lambert s law (Fig. 3). 

A multicomponent calibrator is employed for calibrating the Seralyzer. Two calibrators enable a 2-point calibration. Human serum is used as initial material to which substances have been added by a special preparatory procedure. Thus one of each calibrator is available with concentrations (activities) in the low and in the high range. The concentrations (activities) were determined by means of routine wet chemical methods no details have been stated. Few studies are available on the frequency of calibration, i.e. on its constancy. The U.S. Food and Drug Administration prescribes a seven-day calibration rhythm that has been increased to 14 and 30 days, respectively, for some components. The manufacturer, Bayer Diagnostic, informs us that in future the calibration cycle will be 30 days. 

Bayer Diagnostics Stoke Court Stoke Poges Slough SL2 4LY UK... 

Reference methods for blood gas and electrolyte determinations have been described in detail by the IFCC. A schematic diagram characteristic of a typical instrument is shown in Figure 27-4. Electrochemical principles and structural features of electrodes are discussed in Chapter 4. Prominent manufacturers of blood gas equipment include Roche Scientific Corp., Bayer Diagnostics, Instrumentation Laboratory, Nova Biomedical, and Radiometer America, Inc. Readers are referred to these manufacturers for details and operational features of specific instruments. 

Bayer Diagnostics, T rrytown, NY) NucliSens HIV-1 QT Assay NASBA 176-3,470,000 copies/mL... 

ExacTech Satellite G Glucometer Elite MediSense (USA) Bayer Diagnostics (Germany) glucose glucose glucose 1.1-33.3 2.0-33.3 disposables disposables disposables... 

Ann O Rexia s admission laboratory studies showed a blood glucose level of 65 mg/dL (normal fasting blood glucose = 80 - 100 mg/dL). Her serum ketone body concentration was 4,200 [xM (normal = 70 [xM). The Ketostix (Bayer Diagnostics, Mishawaha, IN) urine test was moderately positive, indicating that ketone bodies were present in the urine. In her starved state, ketone body use by her brain is helping to conserve protein in her muscles and vital organs. 

Fig. 2. hMIP-1 does not affect the duration of thrombocytopenia in a murine model of chemotherapy. The blood samples taken from the animals described in Fig. 1 were analyzed for platelet numbers using a Technicon H 1 analyzer (Bayer Diagnostics, Newbury, UK). 

Fig. 4. Comparison of the neutrophil and monocyte mobilizing activity of BB-10010 in the mouse, rat, and marmoset. BB-10010 (100 pg/kg) was administered subcutaneously to the three species. At various times postdosing, blood samples were taken, anticoagulated with EDTA, and the number of neutrophils and monocytes were analyzed using a Technicon H 1 analyzer (Bayer Diagnostics). The change in circulating cell number relative to placebo treated animals is indicated. Values are the average of at least 4 determinations.

Many IS Es based on solid or Kquid membranes and ion-selective FETs possess sufficiently small Kij values (Eq. 1) toward common interferents, and have been developed into commercial benchtop analyzers that allow the measurement of Na+, K+, Ca +, Cl , HC03, and other ions, in instruments that are designed solely for IS E measurements or in combination with other integrated devices (such as amper-ometric sensors and spectrophotometers) to measure other parameters [7]. Applications of these devices to blood gas analysis have been reviewed recently [81]. Companies that produce this instrumentation for clinical chemistry applications include Abbott Diagnostics, AVL, Bayer Diagnostics, Beckman Coulter, Nova Biomedical, Ortho-Clinical Diagnostics, Boehringer-Mannheim/Roche, and Radiometer [82]. Many instruments allow measurements to... 

Labelled Cobalamin or Labelled Binding Protein. The first protein binding assays for cobalamin employed radiolabelled cobalamin and measured the amount of radioactive cobalamin bound when this label was added alone or in combination with calibrators or the sample to be tested (Rothenberg 1961). The amount of bound label decreased as the concentration of cobalamin in the cahbrator or sample increased. As an alternative to radioactive labels, the commercial companies have developed derivatives of cobalamin still able to bind to the binding protein but at the same time coupled to a property such as fluorescence (Abbott 2007 Bayer Diagnostics 2008). Another approach is to in-solubilize cobalamin and measure the amount of labelled binding protein not trapped on the in-solubilized cobalamin (Roche, 2008). 

Bayer Diagnostics 2008 Roche 2008). One way to do this is to couple the binding protein covalently to solid-phase particles in the form of paramagnetic beads. Another approach is to use biotinylated cobalamin as the competitive agent after binding to the protein, biotinylated cobalamin is precipitated onto streptavidin linked to solid-phase particles. In either case, the protein-cobalamin equilibrium may be disturbed in washing steps, and leakage from the solid phase may also be an issue to consider especially if these analytical principles are used in in-house assays. 

Three Automated Platforms Reacts Differently Towards Changes in Sample Type. This section describes the design of assays for cobalamin from the three main players in automated cobalamin analysis on human serum (Abbott, Bayer Diagnostics and Roche) and demonstrates how these assays react if employed for the measurement of cobalamin in human milk. Human milk contains up to 200-fold more haptocorrin than serum and most of it is unsaturated with cobalamin. If haptocorrin is insufficiently denatured, it can interfere in the assays (Lildballe et al. 2009). 

In the Bayer Diagnostics analyser, cobalamin in the sample mixed with labelled cobalamin competes for binding with in-solubilized intrinsie faetor (Bayer Diagnostics 2008). The presence of active haptocorrin in the sample will give rise to a spurious result that is too high for cobalamin since part of the labelled cobalamin will bind to haptocorrin rather than to the intrinsic factor. 

Bayer Diagnostics, 2008. ADVIA Centaur reference and assay manual. 

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