Nested-PCR and TaqMan real-time quantitative PCR assays for human adenoviruses in environmental waters.

Human adenovirus (HAdV) infections can occur throughout the year. Cases of HAdV-associated respiratory disease have been more common in the late winter, spring, and early summer. In this study, to provide viral pollution data for further epidemiological studies and governmental actions, the presence of HAdV in the aquatic environment was quantitatively surveyed in the summer. This study was conducted to compare the efficiencies of nested-PCR (polymerase chain reaction) and qPCR (quantitative PCR) for detecting HAdV in environmental waters. A total of 73 water samples were collected from Puzi River in Taiwan and subjected to virus concentration methods. In the results, qPCR had much better efficiency for specifying the pathogen in river sample. HAdV41 was detected most frequently in the river water sample (10.9%). The estimated HAdV concentrations ranged between 6.75 × 10(2) and 2.04 × 10(9) genome copies/L. Significant difference was also found in heterotrophic plate counts, conductivity, water temperature, and water turbidity between presence/absence of HAdV. HAdV in the Puzi River may pose a significant health risk.

A simple, innovative way to reduce rhinitis symptoms after sedation during endoscopy.

BACKGROUND: Supplmental oxygen is routinely given via nasal cannula (NC) to patients undergoing moderate sedation for endoscopy. Some patients complain of profuse rhinorrhea and/or sneezing after the procedure, which results in additional medical costs and patient dissatisfaction. OBJECTIVES: To determine the causal relationship between the route of oxygen delivery and troublesome nasal symptoms, and to seek possible solutions. METHODS: Patients (n=836) were randomly assigned to one of the three following groups: the NC group (n=294), the trimmed NC (TNC) group (n=268) and the nasal mask (NM) group (n=274). All received alfentanil 12.5 µg/kg and midazolam 0.06 mg/kg, and adjunct propofol for sedation. Supplemental oxygen at a flow rate of 4 L/min was used in the NC and TNC groups, and 6 L/min in the NM group. The incidence of nasal symptoms and hypoxia were assessed. RESULTS: The incidence of rhinitis symptoms was significantly higher in the NC group (7.1%) than in the TNC (0.4%) and NM (0%) groups (P<0.001). The incidence of hypoxia was lower in the NC group (3.1%) (P=0.040). All hypoxia events were transient (ie, less than 30 s in duration). On spirometry, the mean value of the lowest saturation of peripheral oxygen was found to be significantly lower in the NM group (96.8%) than in the NC group (97.7%) (P=0.004). CONCLUSIONS: Trimming the NC or using NMs reduced the incidence of rhinitis symptoms; however, the incidence of hypoxia was higher. Further investigation regarding the efficiency of oxygen supplementation is warranted in the design of novel oxygen delivery devices.

Induction of hepatic glutathione S-transferase and UDP-glucuronosyltransferase activities by ketamine in rats.

BACKGROUND: Ketamine has been shown to induce rat cytochrome P-450 in a way similar to phenobarbital. However, whether ketamine is able to induce glutathione S-transferase (GST) and UDP-glucuronosyltransferase (UGT), two major phase II drug-metabolizing enzymes, remains unclear. The present study aimed to investigate the effect of ketamine on GST and UGT activities in rats. METHODS: In a dose-response study, male adult Wistar rats were treated with 10, 20, 40 or 80 mg/kg ketamine intraperitoneally twice daily for 4 days. Livers were removed 1 day after ketamine treatment and hepatic GST and UGT activities were determined. In a reversibility study, rats were treated with 80 mg/kg ketamine intraperitoneally twice daily for 4 days and killed 1, 2, 3 or 4 days after the last dose of ketamine. Livers were removed and hepatic GST and UGT activities were determined. RESULTS: The results of the dose-response study showed that treatment of rats with 10, 20, 40, or 80 mg/kg ketamine produced 19%, 20%, 18%, and 25% increases respectively in the catalytic activity of hepatic cytosolic GST, and 41%, 41%, 35%, and 38% increases respectively in the catalytic activity of microsomal UGT. The results of the reversibility study showed that the GST activities of the rats killed 1, 2, 3, or 4 days after ketamine treatment were 62%, 88%, 46% and 65% higher than the activity of the control group. The UGT activities of the rats killed 1, 2, 3, or 4 days after ketamine treatment were 56%, 53%, 54% and 72% higher than the activity of the control group. CONCLUSION: Ketamine is able to induce the activities of hepatic GST and UGT in rats. The induced GST and UGT activities persist for at least 4 days after cessation of ketamine. The results suggest the possibility of interactions of drugs related to phase II enzyme induction in chronic ketamine users.