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Graphene is a highly promising material for biosensors due to its excellent physical and chemical properties which facilitate electron transfer between the active locales of enzymes or other biomaterials and a transducer surface. Printing technology has recently emerged as a low-cost and practical method for fabrication of flexible and disposable electronics devices. The combination of these technologies is promising for the production and commercialization of low cost sensors. In this review, recent developments in organo-functionalized graphene and printed biosensor technologies are comprehensively covered. Firstly, various methods for printing graphene-based fluids on different substrates are discussed. Secondly, different graphene-based ink materials and preparation methods are described. Lastly, biosensing performances of printed or printable graphene-based electrochemical and field effect transistor sensors for some important analytes are elaborated. The reported printed graphene based sensors exhibit promising properties with good reliability suitable for commercial applications. Among most reports, only a few printed graphene-based biosensors including screen-printed oxidase-functionalized graphene biosensor have been demonstrated. The technology is still at early stage but rapidly growing and will earn great attention in the near future due to increasing demand of low-cost and disposable biosensors., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Introduction: Electrophoretic analysis of plasma von Willebrand factor (VWF) multimer distribution and infrastructure is essential for subtyping von Willebrand disease. To improve the sensitivity, precision and efficiency of this assay, we developed and validated a new in-gel infrared fluorescent VWF multimer imaging method to visualize and quantify VWF multimers directly in the agarose gel, thus eliminating electroblotting or autoradiographic steps., Materials/methods: VWF multimer analyses of plasma samples from 34 patients with known von Willebrand disease or acquired von Willebrand syndrome, 9 patients with acquired VWF abnormalities, 26 normal volunteer donors and 49 patient samples referred for von Willebrand factor multimer analysis were performed by both traditional autoradiographic and the new infra-red imaging methods and compared. VWF multimer image data were electronically acquired, archived and analyzed., Results: The in-gel infrared method has a sensitivity of detecting VWF antigen as low as approximately 1.6 IU/dL, a reliable fluorescent intensity with intra- and inter-day variability (CV) of 5% and 6% respectively, and provides superior imaging resolution and shortened test turnaround time. Using intermediate resolution agarose gel electrophoresis, the infra-red method sensitively detects subtle loss of highest molecular weight von Willebrand factor multimers in plasmas with acquired VWF abnormalities and in commercial normal reference plasmas, and provides evidence of increased proteolysis of ultralarge multimers in some type 2 VWD plasmas., Conclusions: The in-gel infrared fluorescent VWF multimer imaging method provides a sensitive, reliable, efficient and robust system to improve laboratory testing for von Willebrand disease classification., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

This 1999 research analyzed selected descriptive variables for consumers with significant disabilities, who were successfully employed. The goal was to investigate employment outcomes for consumers whose cases were closed as successfully employed. Human capital theory provided the theoretical underpinnings for evaluating the findings. This study empirically assessed factors which contributed to increased weekly earnings for consumers of state vocational rehabilitation services with severe disabilities. The variables included in this study were weekly earnings at closure, correlated with year last employed, highest grade completed, and birth year. The study found that 17.2% of variability in weekly earnings of the significantly disabled consumers can be predicted by these variables. Education, age, and work experience were found to be predictors of potential earning power. These findings can be used to provide the foundation for the development of reliable program evaluation as well as clinical interventions. This study links outcomes to the services provided. It further provides the data necessary to support policy development in the areas of rehabilitation and welfare reform.

Exogenous (e.g., environmental) mutagens produce characteristic patterns of mutation. In contrast, endogenous mutation processes likely are associated with an invariant pattern of mutation. Analysis of factor IX gene mutations among large samples of hemophilia B patients from multiple, widely divergent geographic and ethnic populations reveals a remarkably constant mutational pattern, suggesting that the primary germline mutational process results from endogenous processes rather than environmental mutagens. To test this hypothesis further, we have initiated a study of hemophilia B patients from Peru because relatively large populations of AmerIndians can be found with low admixtures of other races. To determine if the factor IX (FIX) germline mutational pattern in AmerIndians differs from the common and putative endogenous pattern, FIX gene mutations were characterized in an initial sample of 10 AmerIndian Peruvian patients with hemophilia B. A minimum of 2.2 kb of the FIX gene was examined by PCR and direct sequencing of all eight exons, the splice junctions, and the promoter region. The pattern of germline mutation in AmerIndians was similar to the pattern of FIX germline mutations from larger U. S. Caucasian or Mexican Hispanic samples (P=0.55 and 0.63, respectively). The similar pattern in this initial sample of the Peru AmerIndian population provides additional support for the inference that the FIX germline mutational pattern results from predominantly endogenous processes rather than exogenous mutagens.

Purpose: We report that treatment of an immune mediated postoperative Factor V (FV) deficiency with intravenous immune globulin (IVIg) resulted in serological and clinical disappearance of the inhibitor., Patients and Methods: A 9-year-old girl was exposed to bovine thrombin during cardiovascular surgery and subsequently developed severe, refractory hemorrhage caused by acquired FV deficiency (FV activity < 5%). Despite blood product transfusions, hemorrhage continued, and the patient was given IVIg, 400 mg/kg daily, for 9 day., Results: Prolonged clotting times immediately trended toward normal, and the hemorrhage ceased by the fifth IVIg treatment day, concomitant with increasing plasma FV activity and disappearance of human FV inhibitor activity. The patient's plasma initially had a much higher inhibitor titer against bovine FV (122-215 Bethesda units) than against human FV (3-4 Bethesda units). Circulating antibodies (IgM and IgG) to bovine and human thrombin and FV were detected by enzyme-linked immunosorbent assay (ELISA). After completion of IVIg treatment, IgG antibodies to bovine FV and thrombin persisted, as did high-titer inhibition of bovine FV, whereas the subpopulation of IgG and IgM antibodies reactive with human FV were undetectable., Conclusions: The inhibitor likely developed from a heterogenetic immune response to bovine FV contaminating the topical thrombin preparation used during surgery. To our knowledge, this is the first demonstration of immunological clearance of an acquired FV antibody associated with the use of IVIg. The data suggest an antiidiotypic mechanism of IVIg in modulating clearance of antihuman FV antibodies.

Levels of three factor VIII-von Willebrand factor components (von Willebrand antigen, ristocetin cofactor, and factor VIII coagulant) were higher in specimens of plasma from 27 patients with giant cell arteritis and 18 patients with polymyalgia rheumatica than in specimens from 21 normal control subjects. Values in patients with active giant cell arteritis were higher than those in patients with either inactive giant cell arteritis or active polymyalgia rheumatica. Levels of factor VIII-von Willebrand factor components tended to decline gradually after disease activity had been suppressed by corticosteroid therapy and therefore may be indicators of vascular damage. These levels, however, did not revert to normal rapidly in response to corticosteroid therapy as did the patients' symptoms and the usual laboratory measurements indicative of inflammation; thus, measurements of these components are unlikely to be useful in day-to-day management of these diseases. Electrophoretic analysis suggested that the elevated values are due to increased amounts of normal factor VIII-von Willebrand factor rather than to the presence of an abnormal molecule.