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Abstract: Using field observations followed by petrological, geochemical, geochronological, and geophysical data, we infer the presence of a previously unknown Miocene subglacial volcanic center ~230 km from the South Pole. Evidence of volcanism is from boulders of olivine‐bearing amygdaloidal/vesicular basalt and hyaloclastite deposited in a moraine in the southern Transantarctic Mountains. 40Ar/39Ar ages from five specimens plus U‐Pb ages of detrital zircon from glacial till indicate igneous activity 25–17 Ma. The likely source of the volcanism is a circular −735 nT magnetic anomaly 60 km upflow from the sampling site. Subaqueous textures of the volcanics indicate eruption beneath ice or into water at the margin of an ice mass during the early Miocene. These rocks record the southernmost Cenozoic volcanism in Antarctica and expand the known extent of the oldest lavas associated with West Antarctic Rift system. They may be an expression of lithospheric foundering beneath the southern Transantarctic Mountains. [ABSTRACT FROM AUTHOR]

Objectives: A common objection to using artificial neural networks in clinical decision support systems is that the reasoning behind diagnostic indications cannot be sufficiently well explained. This paper presents a method for visualizing diagnostic indications generated from an artificial neural network-based decision support algorithm (ANN-algorithm) in conditions developing over time.Methods: The main idea behind the method is first to calculate and graphically present the decision regions corresponding to the diagnostic indications given as output from the ANN-algorithm, in the space of two selected, clinically established 'display variables'. Secondly, the trajectory of time series measurement results of these, often biochemical markers, together with the respective 95% confidence intervals are superimposed on the decision regions. This will permit a nurse or clinician to grasp the diagnostic indication graphically at a glance. The indication is further presented in relation to clinical variables that the clinician is already familiar with, thus providing a sort of explanation. The predictive value of the indication is expressed by the proximity of the measurement result to the decision boundary, separating the decision regions, and by a numerically calculated individualized predictive value.Results: The method is illustrated as applied to a previously published ANN-algorithm for the early ruling-in and ruling-out of acute myocardial infarction, using monitoring of measurement results of myoglobin and troponin-I in plasma.Conclusion: The method is appropriate when there is a limited number of clinically established variables, i.e. variables which the clinician is used to taking into account in clinical reasoning. [ABSTRACT FROM AUTHOR]

Abstract: The influence of coating polystyrene tissue culture plates with different proteins on murine hybridoma cell growth and antibody production was investigated. Fibronectin, collagen I, bovine serum albumin and laminin were used to coat NUNC® and COSTAR® cell culture plates. Cell number and antibody concentration in culture fluids were quantified as indicators for cell viability, proliferation and productivity. Adhesive behaviour, morphology, expression of surface receptors of hybridoma cells and the presence of tyrosine-phosphorylated proteins in cell lysates were characterized by cell adhesion experiments, microscopy, flow cytometry and Western Blot analysis. It was shown that coatings with fibronectin (0.2μg/ml) lead to a substantial improvement of cell growth by 50–70% and an increase of monoclonal antibody production by 100–120%. Collagen I coatings showed an improvement in cell growth by 30–70% and by 60% for the production of monoclonal antibodies. Coatings with BSA and laminin had minor effects on these parameters. It was found that the hybridoma cell lines used in this study did not express the α2-chain of the α2β1-integrin, which is responsible for binding to collagen and laminin. However, the presence of β1-integrin on the cell surface was shown, which should enable hybridoma cells to bind fibronectin. We propose, therefore, that fibronectin adsorption to cell culture materials may be a promising approach to enhance the production of monoclonal antibodies by cultivated hybridoma cells. [Copyright &y& Elsevier]

Biomedical technology has opened up possibilities of treating the failure of internal organs like kidney and liver by artificial organ therapy. Most of these techniques are based on polymer membranes, which allow the removal of excess of water, salts and toxins from the circulation. However, haemodialysis for the replacement of kidney function results in an increased morbidity and mortality of patients after long‐term application. Conventional therapy, such as haemofiltration for the treatment of acute liver failure does not improve significantly the survival rate of patients. Biohybrid organ support as a combination of the artificial organ therapy with the functional activity of immobilised cells seems to be a solution of the problem. Membranes applied in these devices have to face both tissue cells and blood. Organ cells in biohybrid organs have to make intimate contact with the surface of membrane but must also develop close cell–cell‐connections as a prerequisite for their survival and high functional activity. Blood to be detoxified will contact the other side of membrane and may not become activated by the synthetic material. New polymer membranes based on acrylonitrile were developed to address these requirements by tailoring the composition of copolymers and to be applied in a specific hollow fibre bioreactor with an outer fibre for blood contact, and an inner fibre for tissue contact or vice versa. [ABSTRACT FROM AUTHOR]

While surgery is the mainstay of therapy for Peyronie disease requiring correction of angulation, interest has grown in the application of extracorporeal shockwave therapy (ESWT) as a minimally invasive approach. This article reviews the current literature reporting the use of ESWT for Pey ronie disease. [ABSTRACT FROM AUTHOR]

In studies of glucose metabolism in neonates, a commonly used approach is based on constant rate infusion of glucose labelled with a stable isotope in order to reach an approximate steady state with regard to isotopic enrichment in plasma. Under presumed conditions of a glucose steady state, the rates of appearance and disappearance of glucose can, in principle, be calculated with use of a simple steady-state formula. However, in the neonate, steady-state conditions do not generally prevail and results derived on such assumptions are questionable. In the present study, we have taken a pragmatic approach and compared estimates obtained from the conventional formula with values calculated with Steele's non-steady-state method. The results show that the estimated glucose appearance and disappearance rates change more or less over the observed time period in all the typical cases studied, and that "steady-state estimates" may differ from the corresponding non-steady-state values by up to 37%. In a sensitivity analysis, the value of the distribution volume factor was found to be non-critical, a circumstance that supports the use of Steele's method. Thus, even though the classical Steele pool-fraction method for computation of rates of appearance and disappearance under non-steady-state conditions has been criticized, it is still the most realistic alternative to the frequently used simple steady-state formula in applications to newborns. [ABSTRACT FROM AUTHOR]

General specifications of analytical goals for biochemical monitoring have been proposed based on biological within-subject variation. As a complement to this strategy for general global quality requirements there is also a need for other methods and approaches to set more optimal requirements in specific monitoring situations, i.e. application of systems and sensitivity analysis using (i) rules for propagation of errors (uncertainty) in simple algebraic/statistical transformations of laboratory results; (ii) biochemical/pathophysiological simulation models; and (iii) formalized descriptions of clinical classification and decision support processes. The possible gain in medical outcome by improving analytical and preanalytical quality should then be related to the often more important aspects of selection and combination of “tests”, period and frequency of sampling/measurement, and the use of correct conceptual and computational models for transformation of data. [ABSTRACT FROM AUTHOR]

Abstract: The maintenance of endothelial cell (EC) monolayer architecture requires stable adhesions not only between neighboring cells but also between cells and the extracellular matrix. While the influence of biomaterials surface wettability on cell–substratum adhesion is rather well studied, its impact on cell–cell cohesion has not been extensively investigated. In the present study a model system consisting of hydrophilic and hydrophobic glass pre-coated with fibronectin and fibrinogen was used to study the influence of surface wettability on both types of cell adhesions. It was demonstrated that the substrate wettability controls the adhesion and cytoskeletal organization of endothelial cells, which has an impact on the subsequent ability of cells to establish stable cell–cell cohesions. These effects were related to the accessibility of specific domains of the adsorbed proteins. While the hydrophobic substratum promoted cell–cell cohesion, on hydrophilic substrata cell–substrate adhesion was dominant. In addition, evidence for an influence of surface wettability on the cross talk between integrins and cadherins was found. [Copyright &y& Elsevier]

Abstract: Two studies comparing intraduodenal infusion of a levodopa/carbidopa gel with oral treatments in advanced PD patients demonstrated improvement in UPDRS scores and in frequent clinical ratings on a global treatment response scale. Further analysis of data from these studies was performed to find predictive factors related to degree of improvement with infusion. Pearson''s correlation coefficients between measures of improvement and baseline variables were calculated. Using data from one study, a prediction model was designed and was then evaluated using the other study''s data. Correlations were found indicating that patients with more severe symptoms at baseline were most improved after infusion. [Copyright &y& Elsevier]

Presents various studies on methods for analysis and evaluation in the field of medicine. Quantitative determination of human serum cystatin C initial performance data; Specific immuno assay for intact parathyroid hormone on the Elecsys 2010 analyser; Assay for quantification of growth hormone binding protein in human serum.

Membranes for biohybrid organs such as the biohybrid liver support system have to face 2 different environments, namely blood and tissue cells. Accordingly, the respective membrane surfaces must have optimal properties in terms of biocompatibility for blood or tissue. Flat membranes prepared by a phase inversion process from polyetherimide were modified by binding of tris-(hydroxymethyl)-aminomethane to obtain a surface with hydroxyl groups by binding of polyethylene imine to attach a hydrophilic macromolecule with amine groups useful as a spacer for later bonding of further ligands and by attachment of heparin. The binding of the different ligands was successful as monitored by different physicochemical methods. The blood response of plain polyetherimide was comparable to that of polyacrylonitrile, and it could be further improved by the binding of heparin. The tissue compatibility of polyetherimide and its different modifications was compared with commercial cell culture substrate membranes (Millicell) and found to be comparable for polyetherimide and even better after the modification with tris-(hydroxymethyl)-aminomethane. In conclusion, polyetherimide seems to be an interesting material for the production of membranes for application in biohybrid organ systems. [ABSTRACT FROM AUTHOR]

Abstract: Natural polymers, such as hyaluronan, are considered as good candidates to substitute synthetic materials in many biological applications due to their intrinsic biocompatibility for in vitro and living cell experiments. This work describes surface modifications performed over modified hyaluronan derivatives which could help to understand the physical and biochemical cues on the cell-behaviour. A photocrosslinkable methacrylated hyaluronan was microstructured using soft lithography techniques to obtain a microenvironment suitable for cell-behaviour experiments, which might mimic the extra-cellular matrix. In addition, sulphated and non-sulphated oxidized hyaluronan were immobilized on bare substrates and micrometric features of cell adhesive and non-adhesive proteins were patterned by microcontact printing on top of them. The obtained structures were characterized by optical microscopy, profilometry and atomic force microscopy. The stability of structures was tested by immersion in physiological salt solutions. The observed results prove the suitability of the materials and protocols described. [Copyright &y& Elsevier]

Poly(ether imide) (PEI) membranes of which the surface was modified with carboxylic groups were tested in comparison to pure PEI and poly(ethylene terephtalate) (PET) for their ability to support attachment, growth and function of human umbilical vein endothelial cells (HUVEC) with respect to endothelization of the above materials. Flat sheet PEI membranes were modified by covalent binding of iminodiacetic acid (IDA) for different periods of time (1 to 30 min) to obtain surfaces with various content of carboxylic groups. In addition, fibronectin (FN) and fibrinogen (FNG) pre-adsorption on the various membranes were studied for their effect on HUVEC behaviour. The results show a decreased protein adsorption and HUVEC adhesion, growth and function in terms of prostacyclin production with an increase in carboxylic groups. Pre-adsorption of the membranes with FN or FNG promoted activity of HUVEC, which became superior to cells on PET. FN-coated membranes were found to be a better substrate for HUVEC adhesion and prostacyclin production, while on FNG-coated membranes cells grew better. Overall it can be concluded that PEI is a promising materials for endothelial cells immobilization as it is needed for improving the haemocompatibility of cardiovascular devices. [ABSTRACT FROM AUTHOR]

Cell shapes induced by cell–substratum interactions are linked with proliferation, differentiation or apoptosis of cells. To clarify the relevance of specific surface characteristics, we applied self-assembled monolayers (SAM) of alkyl silanes exhibiting a variety of terminating functional groups. We first characterised the SAMs on glass or silicon wafers by measuring wettability, layer thickness and roughness. Water contact angle data revealed that methyl (CH3), bromine (Br), and vinyl (CH=CH2) groups lead to hydrophobic surfaces, while amine (NH2) and carboxyl (COOH) functions lead to moderately wettable surfaces, and polyethylene glycol (PEG) and hydroxyl (OH) groups created wettable substrata. The surfaces were found to be molecular smooth except for one type of NH2 surface. The SDS-PAGE analysis of proteins adsorbed from bovine serum to the SAMs showed less protein adsorption to PEG and OH than to CH3, NH2 and COOH. Immunoblotting revealed that a key component of adsorbed proteins is vitronectin while fibronectin was not detectable. The interaction of human fibroblasts with CH3, PEG and OH terminated SAMs was similarly weak while strong attachment, spreading, fibronectin matrix formation and growth were observed on COOH and NH2. The strong interaction of fibroblasts with the latter SAMs was linked to an enhanced activity of integrins as observed after antibody-tagging of living cells. [Copyright &y& Elsevier]

Presents summaries of symposiums on application of analytical quality to traceability, method validation and control in Scandinavia. Principles for estimation of analytical quality specifications; Methods to set global quality specifications in laboratory medicine; Types of compounds found in chronic liver diseases.