Detection of hepatitis B virus in plasma using flow cytometric analyses of polymerase chain reaction-amplified DNA incorporating digoxigenin-11- dUTP

Blood donations are routinely screened by multiple serologic assays for antigens/antibodies associated with infection by blood-borne viruses, including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1 and HIV-2), and human T-cell lymphotropic virus (HTLV-I and HTLV-II). A direct detection of these viruses would be more effective for the prevention of transfusion- transmitted infections than the indirect measurement of the variable host immune response to these agents. Because the polymerase chain reaction (PCR) for viral gene amplification offers the most sensitive and direct means of detecting viruses in blood, we have developed a nonisotopic PCR procedure for the detection of HBV, chosen as a prototype. The problems, common to previously described PCR methods, of nucleic acid extraction and inhibition of the PCR by plasma proteins were overcome by isolation of HBV from plasma by means of 450-microns polystyrene beads covalently coated with monoclonal antibody to the Pre- S1 region of the viral envelope protein. Detergent lysis and proteinase K digestion of the immunocaptured virions isolated from plasma released the HBV DNA. A modified PCR-amplification protocol, incorporating digoxigenin-labeled dUTP in the amplified gene products followed by hybridization with a specific biotinylated oligonucleotide probe bound to streptavidin-coated 2.8-microns magnetic beads, allowed flow cytometric analyses of HBV-specific PCR products by means of antibodies to digoxigenin labeled with fluorescein isothiocyanate. The endpoint serial dilutions of pedigreed human plasma samples containing chimpanzee infectious dose (CID50) of 10(7) for adw and CID50 of 10(7.5) for the ayw subtypes were compared in repeated testing of PCR products by our immunoreactive bead (PCR-IRB) assay. HBV DNA was consistently detected in a 5 x 10(-10) dilution of each sample. In testing 20 coded specimens of blood donors, with or without serologic markers of HBV infection, the PCR-IRB was specific and more sensitive than the PCR analyses by slot blot hybridization with radioactive probe. The PCR-IRB assay can be adapted for simultaneous detection of multiple blood-borne viruses by an automated flow cytometric analysis system.     

Amino acid sequence of a platelet-binding human anti-DNA monoclonal autoantibody

The complete amino acid sequences of the variable regions of the heavy and light chains of a human IgM monoclonal platelet-binding autoantibody have been determined. This antibody, HF2-1/17, produced by a human x human hybridoma prepared from lymphocytes of a patient with systemic lupus erythematosus and thrombocytopenia, is polyreactive with single-stranded DNA, synthetic polynucleotides, sulfated carbohydrates, and acidic glycolipids isolated from platelet membranes. The heavy chain is of the VHIII subgroup, and the light chain is of the VKI subgroup. The heavy chain is the expression product of the VH26 germline gene. The light chain bears significant homology to other immunoglobulins of known primary structure, including WEA, GAL, HAU, HK101, and DEE. These results suggest that HF2-1/17 may be an autoantibody derived with little or no modification from germline genes. A model of the antibody combining site suggests that arginine 24 and arginine 30 in the light chain (CDR1) interact with a surface defined by phosphate or sulfate groups of the antigen.     

Value‐driven ERM: Making ERM an engine for simultaneous value creation and value protection

Enterprise risk management (ERM) began as an effort to integrate the historically disparate silos of risk management in organizations. More recently, as recognition has grown of the need to cover the upside risks in value creation (financial and otherwise), organizations and practitioners have been searching for the means to do this. Existing tools such as heat maps and risk registers are not adequate for this task. Instead, a conceptually new value‐driven framework is needed to realize the promise of enterprise‐wide coverage of all risks, for both value protection and value creation. The methodology of decision analysis provides the means of capturing systemic, correlated, and value‐creation risks on the same basis as value protection risks and has been integrated into the value‐driven approach to ERM described in this article. Stanford Hospital and Clinics Risk Consulting and Strategic Decisions Group have been working to apply this value‐driven ERM at Stanford University Medical Center.     

In vitro and in vivo study of the efficacy of a new sebum control essence

Background

People with oily skin often suffer from skin problems such as oily face, blackheads, acne, and enlarged pores. It is necessary to regulate oily skin with skin care products.

Aims

To develop an effective sebum control essence to reduce oiliness of skin.

Methods

The composition of the essence was designed in consideration of different oil control mechanism targets. The skin irritation was assessed in 30 volunteers by a single application close patch test. The efficacy of the essence was evaluated by in vitro experiment, short- and long-term clinical trials with over 60 volunteers.

Results

The results of both in vitro and clinical trials showed that the essence had significant oil control and moisturizing effect, the skin oil content decreased by 21.8% within 8 h and 30.05% after 28 days, which indicated that the essence could achieve rapid and persistent sebum control efficacy. In addition, the essence could relieve the problems of enlarged pores, blackheads and whiteheads in long-term use.

Conclusions

The essence developed in this study can alleviate the problems of oily skin from many aspects, and achieve an excellent effect in oily skin regulation. It is suitable for a daily application in oily skin regulation.