Acute Gastroenteritis Controls Research Articles

Analysis on the duration of intestinal detoxification in restaurant employee infected with Norovirus during the outbreak

Objective: To explore the duration of intestinal detoxification and its related factors infected with Norovirus, and to provide scientific evidences for the prevention and control of acute gastroenteritis caused by Norovirus in the future. Methods: Follow up and sampling program on 115 employees in a restaurant outbreak of Norovirus in Chengdu in 2017 was carried out. Anal swab was collected every 3 d or 7 d for nucleic acid detection, and the experimental results were statistically analyzed. Results: The positive rates of Norovirus in restaurant employee were 14.78%, 7.89%, 3.51% and 0.88% on the 7(th), 11(th), 17(th) and 24(th) day, respectively. During the follow-up period, the positive rates of Norovirus decreased as time increased. The positive rate of all employees was up to 14.78% on the 7(th) day. The positive rates had no significant difference between different sex and between different types of work. The duration of detoxification averaged 14.94 days and the maximum of detoxification time was on 28 days. The detoxification period of treatment case was shorter than that of asymptomatic carriers. Conclusions: There were asymptomatic carriers in restaurant employees during the outbreak of Norovirus that their role as a source of infection in the transmission of Norovirus should not be neglected. In the treatment of the epidemic, we should strengthen the sampling and testing of practitioners, and strictly implement isolation measures for positive detection.

Inhibition of Tulane virus replication in vitro with RNA interference.

RNA interference (RNAi), a conserved mechanism triggered by small interfering RNA (siRNA), has been used for suppressing gene expression through RNA degradation. The replication of caliciviruses (CVs) with RNAi was studied using the Tulane virus (TV) as a model. Five siRNAs targeting the non-structural, the major (VP1) and minor (VP2) structural genes of the TV were developed and the viruses were quantified using quantitative real time PCR (qPCR) and tissue culture infective dose (TCID(50) ) assay. Treatment of the cells with siRNA 4 hr before viral inoculation significantly reduced viral titer by up to 2.6 logs and dramatically decreased viral RNA copy numbers and viral titers 48 hr post infection in four of the five siRNAs studied. The results were confirmed by Western blot, in which the major structural protein VP1 was markedly reduced in both the cells and the culture medium. Two small protein bands of the shell (S) and protruding (P) domains of the viral capsid protein were also detected in the cell lysates, although their role in viral replication remains unknown. Since the TV shares many biological properties with human noroviruses (NoVs), the successful demonstration of RNAi in TV replication would provide valuable information in control of acute gastroenteritis caused by human NoVs.

Low Plasma Nitrite in Infantile Hypertrophic Pyloric Stenosis Patients

There is now substantial evidence that reduced expression of neuronal nitric oxide synthase (nNOS) is implicated in the pathogenesis of infantile hypertrophic pyloric stenosis (IHPS). This study aimed to investigate the role of plasma nitric oxide (NO) in patients with IHPS. Blood and pylorous biopsies of 13 IHPS patients were examined. The control group consisted of 19 age-matched healthy infants and 22 age-matched acute gastroenteritis patients. Plasma nitrite (NO(2-)) and nitrate (NO(3-)) levels were detected with an NO analyzer. Pylorus biopsies of 13 IHPS patients were examined for nitric oxide synthase isoform expression. Plasma nitrite levels in the 13 IHPS patients were significantly lower than in the age-matched healthy controls (0.97 +/- 0.19 vs. 3.53 +/- 0.79 microM; P < 0.001) and the acute gastroenteritis controls (0.97 +/- 0.19 vs.1.39 +/- 0.45 microM; P = 0.006). Decreased expression of nNOS in the nerve fibers of the pylorus circular muscle was found in the 13 IHPS patients. The decreased plasma nitrite levels rose to the normal range (3.27 +/- 0.77 M) after pyloromyotomy. There was no significant correlation between plasma nitrite levels and muscle wall thickness in IHPS patients. We conclude that NO is implicated in the occurrence of IHPS and the plasma nitrite level is valuable for the diagnosis of IHPS.