This study’s aim was to develop a specific and sensitive reverse transcription polymerase chain reaction enzyme-linked immunosorbent assay (RT-PCR-ELISA) for hepatitis A virus (HAV). Three concentration methods were compared using samples from cabbage, lettuce, and sesame leaves that were artificially contaminated with HAV. The specificity of the assay was tested against human norovirus, hepatitis E virus, rotavirus, enterovirus, and FCV. The sensitivity and specificity of RT-PCR-ELISA that were targeted to the 5′NCR and VP1 regions of HAV were compared. Nonspecific reactions were not observed. An optimal primer and probe set for RT-PCR-ELISA was selected for each VP1 and 5′NCR. The detection limit of the RT-PCR-ELISA was enhanced by 10–100 fold more than nested RT-PCR. Our new RT-PCR-ELISA was successfully optimized to screen vegetables for HAV contamination with high sensitivity in large samples.

This study aimed to develop a specific and sensitive reverse transcription polymerase chain reaction enzyme-linked immunosorbent assay (RT-PCR-ELISA) for detecting hepatitis E virus (HEV). Eight sets of primers and biotinylated probes designed in the ORF2-ORF3 overlapping region of HEV were tested for sensitivity. The ability of nested reverse transcription polymerase chain reaction (RT-PCR) and RT-PCR-ELISA to detect HEV was compared. RT-PCR-ELISA was 10–100 times more sensitive than nested RT-PCR and could detect 0.01 ng/μl HEV in swine stool samples. In terms of specificity, RT-PCR-ELISA did not falsely detect HEV when other viruses such as hepatitis A virus, rotavirus, norovirus genotype I, norovirus genotype II, and Feline calicivirus were present. Therefore, RT-PCR-ELISA appears to be a sensitive and specific method for detecting HEV.

This study aimed to develop a specific and sensitive duplex reverse transcription polymerase chain reaction enzyme-linked immunosorbent assay (duplex RT-PCR-ELISA) for hepatitis A virus (HAV) and hepatitis E virus (HEV). Duplex RT-PCR-ELISA could detect and differentiate HAV and HEV with specific probes. When ELISA technique was used to detect probe-bound RT-PCR products, duplex RT-PCR-ELISA could detect as little as 0.1 ng/μL HAV and HEV from clinical samples. Human norovirus, enterovirus, poliovirus, murine norovirus and feline calicivirus were used for the specificity test; all were negative. Therefore duplex RT-PCR-ELISA can be used for the simultaneous detection of HAV and HEV in contaminated fecal samples.

Transglutaminase 2 knockout (TGase2(-/-)) mice show significantly reduced inflammation with decreased myofibroblasts in a unilateral ureteral obstruction (UUO) model, but the mechanism remains to be clarified. Nuclear factor-kappa B (NF-kappa B) activation plays a major role in the progression of inflammation in an obstructive nephropathy model. However, the key factors extending the duration of NF-kappa B activation in UUO are not known. In several inflammatory diseases, we and others recently found that TGase 2 plays a key role in extending NF-kappa B activation, which contributes to the pathogenesis of disease. In the current study, we found that NF-kappa B activity in mouse embryogenic fibroblasts (MEFs) from TGase2(-/-) mice remained at the control level while the NF-kappa B activity of wild-type (WT) MEFs was highly increased under hypoxic stress. Using the obstructive nephropathy model, we found that NF-kappa B activity remained at the control level in TGase2(-/-) mouse kidney tissues, as measured by COX-2 expression, but was highly increased in WT tissues. We conclude that TGase 2 gene ablation reduces the duration of NF-kappa B activation in ischemic injury. (C) 2010 Elsevier Inc. All rights reserved.

The prevalence of asymptomatic norovirus (NoV) infection was investigated in children registered for kindergarten in Korea during the winter and summer. Children with no gastrointestinal symptoms, including diarrhea and abdominal pain, during the 2 weeks before and following sample collection were included in this investigation. NoV presence and genetic identification were determined with real-time reverse transcriptase-polymerase chain reaction and conventional nested reverse transcriptase-polymerase chain reaction. The prevalence of NoV in asymptomatic children was 5.5% in the winter and 3.5% in the summer, respectively. GII.4 was the most prevalent NoV genotype, but GII.2 and GI.10 were also found during genetic analysis. This study demonstrates that asymptomatic NoV infection may be an important source of transmission in kindergarten children.

Bacillus cereus is a gram-positive spore-forming bacterium and produces an emetic or diarrheal syndrome induced by an emetic toxin and an enterotoxin, respectively. In this study, the effect of different types of media, temperature, and time on the sporulation of B. cereus, and thermal resistance of B. cereus spores produced in various temperatures were evaluated. The highest levels of spores were detected when they are produced at . There were no significant differences in levels of spores produced at among culture media and times while levels of spores produced at were significantly reduced with the increase of time. However, thermal resistance of B. cereus spores could be affected by incubation temperature. In fact, higher D-values (12.0, 10.1, and 5.9 min for 2,4, and 6 weeks, respectively) of spores produced at were observed than did in samples produced at other temperatures (25 and ). D-values of spores were 7.7, 8.2, and 12.0 min when they were produced at 25,37, and for 2 weeks, respectively. The sporulation of B. cereus at could result in high amounts of spores however the sporulation at for 2 weeks could be effective to produce thermal resistant spores.