Novel DNA sequence isolated from blood donors with high transaminase levels.

Aim:   In Japan, the etiology of 10-20% of cases of acute hepatitis remains unclarified. This study was conducted to verify the agent causing non-A-E hepatitis.

Methods:   Serum samples from 500 blood donors with elevated alanine aminotransferase (ALT) levels were screened by polymerase chain reaction using primers constructed from conserved areas of RNA virus helicase.

Optimization of the virus concentration method using polyethyleneimine-conjugated magnetic beads and its application to the detection of human hepatitis A, B and C viruses.

To enhance the sensitivity of virus detection by polymerase chain reaction (PCR) and reverse transcription PCR (RT-PCR), a novel virus concentration method using polyethyleneimine (PEI)-conjugated magnetic beads was developed in our previous study. However, several viruses could not be concentrated by this method. In this paper, the conditions of virus concentration were optimized to concentrate a wide range of viruses more efficiently.

Virus concentration using polyethyleneimine-conjugated magnetic beads for improving the sensitivity of nucleic acid amplification tests.

To enhance the sensitivity of virus detection by polymerase chain reaction (PCR) and reverse-transcriptional (RT)-PCR, we developed a novel virus concentration method using polyethyleneimine (PEI)-conjugated magnetic beads. PEI-magnetic beads adsorbed efficiently the enveloped viruses Sindbis virus and Herpes simplex 1 virus, and the nonenveloped virus SV-40, but not the nonenveloped viruses porcine parvovirus (PPV) or poliovirus, based on the PCR detection data. Furthermore, the infectivity in the supernatant of former viruses was reduced markedly after incubation with PEI-magnetic beads.

Virus concentration using sulfonated magnetic beads to improve sensitivity in nucleic acid amplification tests.

To enhance the sensitivity of virus detection by polymerase chain reaction (PCR) and reverse-transcriptional (RT)-PCR, we developed a novel virus-concentration method using sulfonated (SO-) magnetic beads in the presence of divalent cations. In the presence of either Zn(2+) or Cu(2+) ions, we showed that SO-magnetic beads were able to concentrate non-enveloped model viruses, such as porcine parvovirus (PPV) and poliovirus, which were not concentrated by polyethyleneimine (PEI)-magnetic beads.(1)) Using the SO-magnetic beads, the sensitivity of virus genome detection by PCR or RT-PCR can be enhanced.